Dyfyniad APA

Warrack, A. J. N. (1971). Points from Letters: Emphysema in Coalworkers.

Dyfyniad Arddull Chicago

Warrack, A. J. N. Points From Letters: Emphysema in Coalworkers. 1971.

Dyfyniad MLA

Warrack, A. J. N. Points From Letters: Emphysema in Coalworkers. 1971.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.