APA (7th ed.) Citation

Block, B. (1966). Do-it-yourself Knudsen gauge. American Journal of Physics, 34, 159.

Chicago Style (17th ed.) Citation

Block, B. "Do-it-yourself Knudsen Gauge." American Journal of Physics 34 (1966): 159.

MLA (9th ed.) Citation

Block, B. "Do-it-yourself Knudsen Gauge." American Journal of Physics, vol. 34, 1966, p. 159.