@inproceedings{inproceedingsc98a4f33,
title   = {State-space approach to spatial variability of soil parameter, symbiotic 'N IND.2'-fixation and crop yield},
author = {Wendroth, O and Kirda, C and Reichardt, Klaus and Nielsen, D R},
year = {1993},
publisher = {Institute of Agrophysics of the Polish Academy of Sciences},
booktitle   = {International Seminar on Agricultural and Environmental Aspects of Soil Structure}
}