共 9 条
[1]
BALCH C C, 1948, Vet Rec, V60, P446
[3]
BECHDEL SI, 1927, B PA AGR EXP STA, V213, P18
[4]
Forbes EB, 1925, J AGRIC RES, V31, P0987
[5]
HELLER VG, 1941, TECH B OKLA AGR EXP, V10
[6]
HOFLUND S., 1948, ONDERSTEPOORT JOUR VET SCI AND ANIMAL INDUST, V23, P395
[7]
KELLNER O, 1907, ERNAHRUNG LANDWIRTSC
[8]
MORROW KS, 1929, B S C AGR EXP STA, V255
[9]
OLSON TM, 1930, B S DAK AGR EXP STA, V252, P42