共 49 条
[31]
MIELCK O, 1913, FUHLINGS LANDW Z, V62, P585
[32]
MITCHERLICH EA, 1910, LANDW JB, V39, P299
[33]
NOLTE O, 1923, FLUGSCHR DEUT LANDW, V23
[34]
PENNY CL, 1905, DEL AGR EXP STA B, V67, P1
[35]
PENNY CL, 1903, DEL AGR EXP STA B, V60, P1
[36]
Potter RS, 1917, J AGRIC RES, V11, P0677
[37]
ROBERTS IP, 1897, NY AGR EXP STA B, V135, P269
[38]
ROBINSON CS, 1923, J OFF AGR CHEM, V5, P446
[39]
ROBINSON TR, 1908, USDA BUR PLANT IND, V15
[40]
SCHNEIDEWIND W, 1915, ERNAHRUNG LANDWIRTSC, P262