共 8 条
[1]
CAMPBELL GA, Patent No. 792248
[2]
CAMPBELL GA, 1904, ELECTR WORLD, V43, P647
[4]
SHACKELTON, 1928, BELL SYSTEM TECH J, V7, P70
[5]
SHACKELTON, 1927, BELL SYS TECH J, V6, P142
[6]
SHACKELTON, 1929, FERGUSON BELL SYS TE, V8, P560
[7]
1904, ELECT WORLD ENG, V43, P647
[8]
1922, BELL SYS TECH J, V1, P18