APA (7th ed.) Citation
(1968). Liquid penetrant testing method. [s.n.].
Chicago Style (17th ed.) Citation
Liquid Penetrant Testing Method. [s.l.]: [s.n.], 1968.
MLA (9th ed.) Citation
Liquid Penetrant Testing Method. [s.n.], 1968.
Warning: These citations may not always be 100% accurate.