by Niegel, W
Published in Chronica horticulturae (01.03.1994)

by Niegel, W
Published in Acta horticulturae (1988)

by Niegel, W
Published in Acta horticulturae (1992)

by Niegel W
Published in Erwerbsobstbau (1984)

by Niegel, W
Published in Erwerbsobstbau (1984)

by Niegel W, Luedders P
Published in Erwerbsobstbau (1984)

by Gutschick, V.P. (New Mexico State University, Las Cruces, NM), Wiegel, F.W
Published in The American naturalist (01.07.1988)

by Niegel, W. (Instituto Nacional de Investigaciones Agropecuarios, Quito (Ecuador). Dept. de Fruticultura)
Published in Acta Horticulturae (Netherlands) (1988)

by Niegel, W. (Proyecto Fruticultura COTESU/INIAP, Quito (Ecuador))
Published in Acta Horticulturae (Netherlands) (01.09.1992)