共 6 条
[1]
[Anonymous], 1979, LANCET, V2, P83
[3]
WADDELL G, 1982, BRIT J HOSP MED, V28, P187
[4]
Watkinson S, 1984, Radiography, V50, P189
[5]
1983, WHO TECHNICAL REPORT, V689
[6]
1980, LANCET, V2, P1234