by Knauer N, Henrichsmeyer W, Fischbeck G, Langholz H. J, Moosmayer H. U. (comps.)
Published in Agrarspectrum (Germany). no. 13 (1987)

by Schoen H, Sommer C, Steinkopf H, Piotrowski J
Published in Agrarspectrum (Germany). no. 13 (1987)

by Koehne M
Published in Agrarspectrum (Germany). no. 13 (1987)

by Knauer N
Published in Agrarspectrum (Germany). no. 13 (1987)

by Langholz H. J
Published in Agrarspectrum (Germany). no. 13 (1987)

by Hanns H
Published in Agrarspectrum (Germany). no. 13 (1987)