Peer-Reviewed Publications: 
Heller, R., V. Cercasov, and W. v. Engelhardt, 1986: Retention of fluid and particles in the digestive tract of the Llama. Comp. Biochem. Physiol. 83A, No. 4, 687-691.
Lechner, M., R. Heller, V. Cercasov und W. v. Engelhardt, 1986: Partikelgroeßen und Verweilzeiten im Magendarmkanal bei Kamelen im Vergleich mit Rindern und Schafen, J. Anim. Physiol. a. Anim. Nutr. 56, 144.
Haas, U., and M. Jaeger, 1986: Degree of esterification of pectins determined by photoacoustic near infrared spectroscopy. J. Food Science 51, 1087-1089.
Haas, U., 1986: Study of the liquid-gas boundary of water and alcohols by photoacoustic spectroscopy. Can. J. Phys. 64, 1063-1066. 
Wieser, P., and R. Wurster, 1986: Application of the laser microprobe mass analysis to particle collections. In physical and chemical characterization of individual airborne particles. Spurny, K. R. (Ed.), Ellis Horwood Ltd. Chichester UK.
Contributions to Conferences:
Bauer, H. E., and H. Seiler, 1986: Surface analysis by secondary electron spectroscopy. Proc. XIth Int. Cong. On Electron Microscopy, Kyoto, 141-142.