Eastman, N. (1984). Underwater communication: Hand signal for scuba divers (2nd ed.). Princeton Book.
Dyfyniad Arddull ChicagoEastman, Norris. Underwater Communication: Hand Signal for Scuba Divers. 2nd ed. Princeton: Princeton Book, 1984.
Dyfyniad MLAEastman, Norris. Underwater Communication: Hand Signal for Scuba Divers. 2nd ed. Princeton Book, 1984.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.