Consulting services

Art technological laboratory

Our expertise is in the field of minimal invasive and non-destructive analyses on art and cultural heritage objects serving education, art conservation science and, practical conservation and restoration of our cultural heritage. The enormous variety and combination of materials present in cultural objects requires a combined approach of multiple analytical techniques. These challenges are faced with a synergetic combination of methods, infrastructure and research. Would you like to know more? We will try to find out more for you!

Nadim C. Scherrer, PhD in Earth Science

Head of the analytical laboratory and lecturer in the field of instrumental analysis. The main expertise is in scanning electron microscopy combined with elemental analysis, Raman spectroscopy (focus on pigment identification) and light optical microscopy.

Stefan Zumbuehl, PhD in Conservation Science

Researcher and lecturer in the field of art conservation science. The main expertise is minimal invasive analytical techniques using infrared spectroscopy (FTIR) and imaging IR-spectroscopy (FTIR-FPA imaging) and development of sample preparation techniques to push the limits of FTIR (i.e. derivatisation techniques for vibrational spectroscopy).

Thomas Becker, Konservator-Restaurator SKR® und Materialprüfer RT1

Lecturer in the field of non-destructive, imaging techniques (imaging beyond the visible) using UV, NIR and X-radiation. The main expertise is the application of radiography to art and cultural objects in the lab and on-site.

Karin Wyss Heeb, Chemistry, paint and lacquer laboratory technician, (Chemicals contact person)

Responsible for the delivery of chemicals. Contact person for laboratory safety, wet chemistry, GC-MS or DT-MS, climate chambers.

The art technological laboratory HKB serves

  • Education within the (BA and) MA programs of Conservation & Restoration of the Swiss CRC with majors in the fields of ‘paintings and sculptures’, ‘books, graphics, and photographic objects’, ‘architecture, furniture and furnishings’, ‘modern materials and media’ (all at BUA), archaeological and technical heritage (HE-ARC, Neuchâtel), Textiles (The Abegg-Foundation, Riggisberg), stucco and wall paintings (SUPSI-DACD, Lugano),
  • Research in the field of art conservation science,
  • External services for museums, conservators and restorers, cultural heritage preservation as well as external researchers

There is a close collaboration with the analytical laboratory of the Swiss Institute for Art Research in Zurich SIK-ISEA.

The BUA analytical lab routinely deals with the wide range of organic and inorganic materials present in art and cultural heritage. Within this context, we focus our analytical facilities and expertise on material and imaging analytical techniques to research e.g.

  • paint layers (pigments, fillers, binding media) and their stratigraphy and relative chronology
  • the composition of materials present in art objects
  • degradation phenomena within the context of conservation questions
  • the reconstruction of the relative succession of multiple interventions
  • for the documentation of the current condition and judgment of the effects of potential measures - and identify synthetic organic pigments and mixtures thereof
  • towards the optimisation and further development of analytical techniques serving advances in art conservation science
  • towards the compilation of historic reference materials
  • ... 

Please do not hesitate to ask, we will do our best to help you on with our facilities and expertise. 

The HKB analytical laboratory offers modern analytical facilities for light and electron optical microscopy, vibrational spectroscopy, imaging techniques, thermo-analytical techniques, climate simulation, tensile testing and wet chemical techniques.


Microscopes, digital imaging

  • Scanning electron microscope ZEISS EVO MA 10 (VP-SEM) equipped with SE and HDBSD dector systems
  • Digital microscope Keyence VHX1000 equipped with objectives VH-Z20R and VH-Z100R, a VHX-S50 stage with motorised z-axis (1µm step)
  • Various light optical microscopes for stereo-, polarisation- and fluorescence microscopy
  • Digital microscope camera Jenoptik ProgRes XT Core 3 (2080x1542pixel, USB 3)
  • Software ProgRes Capture Pro 2.10 and Helicon Focus


Infrared-, Raman-, UV-Vis-, and energy dispersive spectroscopy

  • FTIR Perkin Elmer System 2000 (10'000 – 580cm-1)
  • FTIR Bruker Tensor 27 (8000 – 400cm-1) & Hyperion 3000 (FPA 64x64, 4000 – 900cm-1)
  • Raman Renishaw InVia (Lasers: 785, 633, 514nm)
  • UV-Vis Spectrophotometer Perkin Elmer Lambda 650
  • EDS Thermo Noran System 7 (SDD 30mm2) attached to a Zeiss Evo MA10 VP-SEM

Imaging Techniques

FTIR-FPA imaging, scanning electron microscopy, Raman mapping, X-radiograpy, IR-thermography, reflectography

  • ATR-FTIR-FPA imaging (Bruker Hyperion 3000, 64x64pixels covering 32x32microns)
  • SEM -SE, -BSE, -EDS (Zeiss Evo MA10 VP-SEM with a Thermo Noran System 7 EDS)
  • Raman mapping (Renishaw InVia, Prior motorised x-y-z stage. 0.04µm step)
  • Mobile analog X-ray radiography

X-ray radiography

Radiography of art and cultural objects

  • Mobile analog X-ray radiography system (GE Inspection Technologies ERESCO 42MF3.1, 5-200kV, 900W, 0.8mm Be)
  • Film processor AGFA Structurix NDT-M
  • M-GIL (Gilardoni) dosimeter

Thermoanalytical techniques

Chemiluminescence, differentialcalorimetry, thermogravimetry

  • CL (ACL Instruments CL1.0 V.5)
  • DSC (Mettler Toledo DSC822e)

Materials testing

Tensile testing, temperature, light ageing

  • Tensile tester (Zwick  BZ2.5/TN1S)
  • Climate chamber (Vötsch VC0020, –10 to 100°C 100–98%rF)
  • Xenotester (Alpha Xenotest Alpha LM)
  • Tube furnace (bis max. 1150°C)
  • Heating,drying and vacuum ovens (up to max. 200–250°C)
  • Video-based optical contact angle measuring system (Dataphysics) OCA-Series

Wet chemistry

Wet chemistry laboratory equipped for education and research

  • 3 fume hoods
  • precision balances
  • pH-meter
  • centrifuge


Equippment for embedding, cutting, lapping, polishing, coating and surface fluorination

  • Blue light curing
  • Wet cutting machine (Scandia Minicut 40), diamond coated disc (127x0.4mm)
  • Grinding and polishing machine (Scandia Scandimatic)
  • C-evaporation coater (Cressington Carbon Coater 108C)
  • Au-evaporation coater (Edwards E12 E2)
  • Au-sputter coater (Edwards S150 with Ar-Plasma)


Moretti, P., Zumbühl, S., Scherrer, N., Piqué, F. (2023). Traditional and modern pigments in Gino Severini's Swiss murals Color Research & Application, pp. 1-20. Wiley-Blackwell 10.1002/col.22870


Müller, L., Henniges, U., Schultz, J., Wöllner, A., Zumbühl, S., Brückle, I. (2022). Pressure-sensitive Tape Removal in Paper Conservation: A Review Journal of Paper Conservation, 23(2), pp. 59-75. Taylor & Francis 10.1080/18680860.2022.2060000

Konietzny, M., Dudew, E., Haller, U., Scherrer, N., Soppa, K. (2022). Klebstoffgitter aus Methylcellulosen für die Konservierung textiler Bildträger: Anwendungseigenschaften und Kennwerte im Vergleich zu Verklebungen mit BEVA® 371-Filmen ZKK - Zeitschrift für Kunsttechnologie und Konservierung(1), pp. 180-194. Wernersche Verlagsgesellschaft

Groetsch, A., Stelzl, S., Nagel, Y., Kochetkova, T., Scherrer, N., Ovsianikov, A., Michler, J., Pethö, L., Siqueira, G., Nyström, G., Schwiedrzik, J. (2022). Microscale 3D Printing and Tuning of Cellulose Nanocrystals Reinforced Polymer Nanocomposites Small, 19(3), p. 2202470. Wiley-VCH10.1002/smll.202202470


Zumbühl, S., Zindel, C., Soulier, B. (2021). Varnish Technology during the 16th–18th Century: The Use of Pumice and Bone ash as Solid Driers Journal of Cultural Heritage, 47(47), pp. 59-68. Elsevier 10.1016/j.culher.2020.10.001

Moretti, P., Zumbühl, S., Caruso, O., Gammaldi, N., Iazurlo, P., Piqué, F. (2021). The Characterization of the Materials Used by Gino Severini in His 20th C Wall Paintings at Semsales in Switzerland, Applied Sciences Applied Sciences

Hofmann, C., Schaefer, I., Zumbühl, S., Ferreira, E. (2021). Einblick zur Farbveränderung in Laubdarstellungen, Kunsttechnologische Untersuchungen an zwei flämischen Landschaftsgemälden des 17.Jahrhunderts Zeitschrift für Kunsttechnologie und Konservierung

Hélou-de La Grandière, P., Boon, J.J., Scherrer, N., Zumbühl, S. (2021). Soulages’ Peinture 12 March 1960: diagnostic analytical studies and tentative consolidation of major curled-up delamination areas. Meddelelser om Konservering, 1, pp. 65-79. Nordiska Konservator Foerbundet, Nordisk Konservator Forbund.

Haudenschild, M., Soppa, K., Zumbühl, S., Scherrer, N., Becker, T., Wyer, P. (2021). Von Weiss zu Schwarz – Der Inkarnatfarbenwechsel der Einsiedler Madonna und ausgewählter Kopien. Zeitschrift für Kunsttechnologie und Konservierung, 34(2021/1), pp. 197-205. Wernersche Verlagsgesellschaft Worms

Scherrer, N., Kocsis, M., Dariz, P., Gervais, C. (2021). Sequential SEM imaging of microbial calcite precipitation consolidation treatment The European Physical Journal Plus, 136(5), pp. 1-10. Springer 10.1140/epjp/s13360-021-01497-7

Hendriks, L.S., Hajdas, I., Scherrer, N., Zumbühl, S., Stenger, J., Welte, C., Synal, H.-A., Günther, D. (2021). Advances and limitations of 14C dating in the field of heritage sciences Technè(52), pp. 111-117. Centre de recherche et de restauration des musées de France 10.4000/techne.10278


Plackett, B. (2020). New chemical analysis allows for less invasive dating of artwork. Carbon dating of lead white paint from canvas edges could help uncover forgeries Chemical & Engineering News, 98(22) American Chemical Society

Hendriks, L., Caseri, W., Ferreira, E.S.B., Scherrer, N., Zumbühl, S., Küffner, M., Hajdas, I., Wacker, L., Synal, H.-A., Günther, D. (2020). The Ins and Outs of 14 C Dating Lead White Paint for Artworks Application Analytical Chemistry, 92(11), pp. 7674-7682. ACS American Chemical Society 10.1021/acs.analchem.0c00530

Caroselli M., Zumbühl S., Cavallo G. & Radelet T. (2020). Composition and techniques of the Ticinese stucco decorations from the 16th to the 17th century: results from the analysis of the materials. Heritage Science 8:102.


Hendriks, L., Hajdas, I., Ferreira, E.S..B., Scherrer, N., Zumbühl, S., Küffner, M., Carlyle, L., Synal, H.-A., Günther, D. (2019). SELECTIVE DATING OF PAINT COMPONENTS: RADIOCARBON DATING OF LEAD WHITE PIGMENT Radiocarbon, 61(2), pp. 473-493. Cambridge University Press 10.1017/rdc.2018.101

Hendriks, L., Hajdas, I., Ferreira, E.S..B., Scherrer, N., Zumbühl, S., Smith, G.D., Welte, C., Wacker, L., Synal, H.-A., Günther, D. (2019). Uncovering modern paint forgeries by radiocarbon dating Proceedings of the National Academy of Sciences of the United States of America, 116(27), pp. 13210-13214. National Academy of Sciences (NAS) 10.1073/pnas.1901540116


Cato, E., Rossi, A., Scherrer, N.C. and Ferreira, E.S.B. (2018). «An XPS study into sulphur speciation in blue and green ultramarine.» Journal of Cultural Heritage 29: 30-35. DOI:10.1016/j.culher.2017.09.005

Hendriks, L., Hajdas, I., Ferreira, E.S.B., Scherrer, N.C., Zumbuehl, S., Küffner, M., Wacker, L., Synal, H.-A. and Günther, D. (2018). «Combined 14C analysis of canvas and organic binder for dating a painting.» Radiocarbon 60(1): 207-218. DOI:10.1017/RDC.2017.107 


Cato, E., Scherrer, N. and Ferreira, E.S.B. (2017). «Raman mapping of the S3- chromophore in degraded ultramarine blue paints.» Journal of Raman Spectroscopy 48(12): 1789-1798. DOI: 10.1002/jrs.5256

Zumbühl, S., Hochuli, A., Soulier, B. and Scherrer N.C. (2017). Fluorination technique to identify the type of resin in aged vanishes and lacquers using infrared spectroscopy. Microchemical Journal 134, 317-326.

Zumbühl, S., Brändle, A., Hochuli, A., Scherrer, N.C. and Caseri, W. (2017). Derivatization Technique To Identify Specifically Carbonyl Groups by Infrared Spectroscopy: Characterization of Photooxidative Aging Products in Terpenes and Terpeneous Resins. Analytical Chemistry 89(3): 1742-1748. DOI:10.1021/acs.analchem.6b04008


Dietemann P., Neugebauer W., Baumer U., Fiedler I., Beil C., Obermeier A., Schäfer S., Zumbühl S., (2016). Analysis of Complex Binding Media Combining Chromatographic Techniques, Fluorescent Staining for Proteins and FTIR-FPA Imaging. In: Painting in Tempera, c. 1900, KUNSTmaterial 4, Beltinger K., Nadolny J. (Eds.), Schweizerisches Institut für Kunstwissenschaft SIK-ISEA Zürich, Archetype Publications, Zürich: 183-203.

Ferreira S.B., Wyss K., de Villemereuil V., Beltinger K., Marone F., Scherrer N.C. and Zumbühl S. (2016). The role of reconstructions in the identification of a wax/resin/gum tempera binder developed by Hermann Urban in 1901 and used by Cuno Amiet in 1902. In: Painting in Tempera, c. 1900, KUNSTmaterial 4, Beltinger K., Nadolny J. (Eds.), Schweizerisches Institut für Kunstwissenschaft SIK-ISEA Zürich, Archetype Publications, Zürich: 205-227.

Hendriks L., Hajdas I., McIntyre C., Küffner M., Scherrer N.C. and Ferreira E.S.B. (2016). Microscale radiocarbon dating of paintings. Applied Physics A 122:167.


Engel N.L. and Zumbühl S. (2015). An evaluation of selected retouching media for acrylic emulsion paint. Journal of the American Institute for Conservation 54(4): 224-237.

Gervais C., Languille M.A., Moretti G., Reguer S. (2015): X-ray photochemistry of Prussian blue cellulosic materials: evidence for a substrate-mediated redox process. Langmuir 31: 8168

Ferreira E., Gros D., Wyss K., Scherrer N., Zumbühl S. and Marone F. (2015). Faded shine…. The degradation of brass powder in two nineteenth century paintings. Heritage Science 3(1): 1-11.


Gervais C., Languille M.A., Reguer S., Garnier C. and Gillet M. (2014): Light and anoxia fading of Prussian blue dyed textiles. Heritage Science 2: 26.

Zumbuehl S., Scherrer N.C. and Eggenberger U. (2014). Derivatization technique to increase the spectral selectivity of two-dimensional Fourier transform infrared focal plane array imaging: Analysis of binder composition in aged oil and tempera paint. Applied Spectroscopy 68(4): 458-465.

Zumbühl S. (2014). Parametrization of the solvent action on modern artists’ paint systems. Studies in Conservation 59(1) 24-37.

Zumbuehl S., Scherrer N.C. and Mueller W. (2014). Derivatisation technique for infrared spectroscopy – characterisation of oxidative ageing products in modern oil paints. In Issues in contemporary oil paint. K. J. Van den Berg, A. Burnstock, M. de Keijzer et al., Springer Verlag: 213-225.

Franken V., Heydenreich G., Jägers E., Müller W., Schulz J. and Zumbühl S. (2014). Set Back the Race: Treatment Strategies for Running Oil Paint. In Issues in contemporary oil paint. K. J. Van den Berg, A. Burnstock, M. de Keijzer et al., Springer Verlag: 333-349.

Blumenroth D., Zumbuehl S., Scherrer N.C. and Mueller W. (2014). Sensitivity of modern oil paints to solvents: effects on synthetic organic pigments. In Issues in contemporary oil paint. Van den Berg K.J., Burnstock A., de Keijzer M. et al., Springer Verlag: 351-362.

Zumbuehl S., Scherrer N.C., Engel N.L. and Mueller W. (2014). The kinetics of dissolution of varnishes: The influence of vapour pressure on the rate of solvent action. ICOM-CC 17th Triennial Conference, Melbourne, International Council of Museums.


Gervais C., Languille M.A., Reguer S., Gillet M., Pelletier S., Garnier C., Vicenzi E.P. and Bertrand L. (2013): Why does Prussian blue fade? Understanding the role(s) of the substrate. Journal of Analytical Atomic Spectrometry 28: 1600-1609.

Becker T. (2013). Die Kunst der Durchstrahlung von Kunst und Kulturgut. Schweisstechnik/Soudure, Offizielles Organ des Schweizerischen Vereins für Schweisstechnik, Ausgabe 01/2013: 17-20.

Blumenroth D., Zumbuehl S., Scherrer N.C. and Mueller W. (2013). Lösemittelsensitivität moderner Ölfarben - Empfindlichkeit synthetisch-organischer Pigmente in Künstlerfarben des 20. Jahrhunderts. Zeitschrift für Kunsttechnologie und Konservierung 27(1): 127-135.


Wörle M, Hubert V., Hildbrand E., Hunger K., Lehmann E., Mayer I., Petrak G., Pracher M., von Arx U. and Wülfert S. (2012). Evaluation of decontamination methods of pesticide contaminated wooden objects in museum collections: Efficiency of the treatments and influence on the wooden structure. Journal of Cultural Heritage 13 (3) Supplement 209-215.

Becker T. (2012). Radiografie von Kunst und Kulturgut. ZfP-Zeitung, Zeitschrift der DACH-Gesellschaften DGZfP, ÖGfZP und SGZP, ISSN 1616-069X, Ausgabe 128: 50-52.

Scherrer N.C. and Zumbuehl S. (2012). Naturwissenschaftliche Ergebnisse. In Degradation an Hinterglasmalerei - vergleichende materialtechnologische Untersuchungen und Klassifizierung der Schadensbilder an Hinterglasgemälden des 18. Jahrhunderts. Bigler J. Bern, Hochschule der Künste Bern: 65-69.

Soulier B., Zumbuehl S., Echard J.-P., Scherrer N.C. and Wyss K. (2012). Resonanzen vergessener Oberflächen: Lautenfirnisse der Renaissance Teil 2. Zeitschrift für Kunsttechnologie und Konservierung 26(2): 462-471.


Becker T. (2011). Verborgenes Entdecken, Artikel über die Radiografie von Kunst und Kulturgut in: Nike-Bulletin 1-2: 24-27.

Zumbuehl S., Scherrer N.C., Ferreira E.S.B., Hons S., Mueller M., Kuehnen R. and Navi P. (2011). Accelerated ageing of drying oil paint: an FTIR study on the chemical alteration: problems of accelerated ageing under variable conditions of light, temperature and relative humidity. Zeitschrift für Kunsttechnologie und Konservierung 25(2): 339-351.


Zumbuehl S., Ferreira E.S.B., Scherrer N.C. and Schaible V. (2010). The non-ideal action of binary solvent mixtures on oil and alkyd paint, Cleaning 2010 – New Insights into the Cleaning of Paintings, Preprints containing the abstracts of the international conference, Valencia 26.-28. May 2010, L. Fuster-Lopez, E.A. Charola, M.F. Mecklenburg, M.T. Domenénech-Carbo (Eds.), Universidad Polytecnica de Valencia and Smithonian Institute, Valencia (2010) 43-44.

Zumbuehl S. and Scherrer N.C. (2010). Die Auswirkungen der morphologischen Strukturveränderungen auf die Materialeigenschaften von Dispersionsfarben. Zeitschrift für Kunsttechnologie und Konservierung 24(1): 76-87.


Ferreira E.S.B., Boon J.J., van der Horst J., Scherrer N.C., Marone F. and Stampanoni M. (2009). 3D Synchrotron x-ray microtomography of paint samples. Proceedings SPIE 7391(Optics for Arts, Architecture, and Archaeology II, Munich, 15 July 2009): 73910L73911-73918.

Scherrer N.C., Zumbuehl S., Delavy F., Fritsch A. and Kuehnen R. (2009). Synthetic organic pigments of the 20th and 21st century relevant to artist's paints: Raman spectra reference collection. Spectrochimica Acta Part a-Molecular and Biomolecular Spectroscopy 73(3): 505-524.

Zumbuehl S., Scherrer N.C., Berger A. and Eggenberger U. (2009). Early Viridian pigment composition characterization of a (hydrated) chromium oxide borate pigment. Studies in Conservation 54(3): 149-159.

Käser F. and Bohn M. (2009). Decomposition in HTPB bonded HMX followed by heat generation rate and chemiluminescence. Journal of thermal Analysis and Calorimetry 96 (3) 687-695.

Zumbühl S., Gross M. (2009). Alexej von Jawlensky, Wassily Kandinsky – Eine Künstlerfreundschaft aus materialtechnologischer Sicht. Reihe Bild und Wissenschaft – Forschungsbeiträge zu Leben und Werk Alexej von Jawlenskys, Band 3, Alexej von Jawlensky Archiv Locarno 256-263.

Zumbühl S., Segieth-Wuelfert F., Wuelfert S. (2009). Die Spitze des Eisbergs... – Kunsttechnologie und Fälschungsproblematik. Reihe Bild und Wissenschaft – Forschungsbeiträge zu Leben und Werk Alexej von Jawlenskys, Band 3, Alexej von Jawlensky Archiv Locarno 252-255.


Comiotto A. (2008). Miniaturized cold atmospheric plasma for the conservation of plastics in modern and contemporary art. Chimia 62 (11) 877-881.

Käser F. and Roduit B. (2008). Lifetime prediction of rubber using the chemiluminescence approach and isoconversional kinetics. Chimia 62 (11) 908-912.

Buder A. (2008). Dammar resin degradation revisited. Chimia 62 (11) 913-917.

Käser F. and Roduit B. (2008). Prediction of the ageing of rubber using the chemiluminescence approach and isoconversional kinetics. Journal of Thermal Analysis and Calorimetry 93 (1) 231-237.

Zumbuehl S., Attanasio F., Scherrer N.C., Mueller W., Fenners N. and Caseri W. (2008). Solvent action on dispersion paint systems and the influence on the morphology-changes and destruction of the latex microstructure. Postprints of the Symposium; Modern Paint Uncovered, Tate Modern London, Tom Learner (Ed.), 17-19. May 2006, Tate Modern 255-266.

Zumbühl S. (2008). Material choice in the context of the artistic working phase – the use of synthetic organic colorants by Alexej von Jawlensky (1864-1941), Preprints, Scientific Workshop at the Doerner Institute München, Germany: „Permanent Yellow, Irgazine Red, Heliogen Blue and Co.: Towards an Improved Micro-identification of Synthetic Organic Pigments and Dyestuffs in Works of Modern Art“, 12. Sept. (2008).

Fuesers O., Zumbühl S. (2008). The Influence of Organic Solvents on the Mechanical Properties of Alkyd and Oil Paint, NDT Database & The e-Journal of Nondestructive Testing, Conference Proceeding, ART2008 – 9th International Conference, May 25-30 2008, Jerusalem,, 219Fuesers.pdf, 1-14.

Kilchhofer M. and Scherrer N.C. (2008). Konservierung von Malereien auf Lehmputzen. Zeitschrift für Kunsttechnologie und Konservierung 22(2): 343-354.


Segieth-Wuelfert F., Wuelfert S. und Zumbuehl S. (2007). Der Teufel steckt im Detail – Der Beitrag der Kunsttechnologie bei der Weiterführung des Catalogue Raisonné Alexej von Jawlensky. Zeitschrift für Kunsttechnologie und Konservierung 21(2): 330-335.


Fuesers O. and Zumbuehl S. (2006). Vorsicht bei der Beleuchtung! Die spezifische Empfindlichkeit von Spätwerken Alexej von Jawlenskys – Untersuchungen zu maltechnisch bedingten Strukturveränderungen. Reihe Bild und Wissenschaft, Forschungsbeiträge zu Leben und Werk Alexej von Jawlenskys, Band 2, 103-110.


Zumbuehl S. and Scherrer N.C. (2003). Aktive Passivierung der Degradation cellulotischer Strukturgefüge. Zeitschrift für Kunsttechnologie und Konservierung 17(1): 387-396.

Dietemann P., Kälin M., Zumbühl S., Knochenmuss R., Wülfert S. and Zenobi R. (2001). A mass spectrometry and electron paramagnetic resonance study of photochemical and thermal aging of triterpenoid varnishes. Analytical Chemistry 73(9) 2087-96.

Dietemann P., Meisterhans C., Pfeiffer C., Zumbühl S., Knochenmuss R. and Zenobi R. (2000). Artificial Photoaging of Triterpenes Studied by Graphite-Assisted Laser Desorption/Ionization Mass Spectrometry. Helvetica Chimica Acta 83(8) 1766-1777.

Zumbühl S. and Wuelfert S. (2001). Chemical Aspects of the Bookkeeper Deacidification of Cellulosic Materials: The Influence of Surfactants. Studies in Conservation 46(3) 169-180.