O-ring Test US PAT 1993 by PROF. Y. OHMURA/การทดสอบโอริง US PAT 1993 โดย PROF Y. OHMURA

PROF YOSHIAKI OHMURA, Pres. of NY MEDICAL COLLEGE (USA)
MEMBER of Japan Helical Science Society 

Bi-Digital O-Ring Test
http://bdort.org/
http://www.icaet.org/
http://www.bdort.net/

O ring test
https://ja.wikipedia.org/wiki/O-%E3%83%AA%E3%83%B3%E3%82%B0%E3%83%86%E3%82%B9%E3%83%88

O－リングテスト入門
http://www.kawade.co.jp/np/isbn/9784309270791/