共 3 条
[1]
GOLDBERG L, 1947, SVENSK TANDLAK T, V40, P819
[2]
GORDH T., 1948, SVENSKA LAKARTIDNINGEN, V45, P116
[3]
Lofgren N. M., 1948, US Pat, Patent No. [Patent 2441498A, 2441498, 2,441,498]