@misc{petersen_assessment_of_2002, 
author={Petersen, W.,Callies, U.},
title={Assessment of Primary Production by Statistical Analysis of Water-quality Data},
year={2002},
howpublished = {journal article},
note = {Online available at: \url{} (DOI). Petersen, W.; Callies, U.: Assessment of Primary Production by Statistical Analysis of Water-quality Data. Acta Hydrochimica et Hydrobiologica. 2002. vol. 30, no. 1, 34-40.}}