Spherical Lapping of Both Bulb and Stem for Electronic Tubes
電子管バルブ・ステムの球面ラッピング

Ichiro IDA, Yuzo ARAI
1957 Journal of the Japan Society of Precision Engineering  
doi:10.2493/jjspe1933.23.585 fatcat:scp26vsbm5cnhd732nnwublbea