MLA

Snodgrass, Mary Ellen. Historical Encyclopedia of Nursing. Santa Barbara, Calif.: ABC-CLIO, 1999.

APA

Snodgrass, M. Ellen. (1999). Historical encyclopedia of nursing. Santa Barbara, Calif.: ABC-CLIO.

Chicago

Snodgrass, Mary Ellen Historical Encyclopedia of Nursing. Santa Barbara, Calif.: ABC-CLIO, 1999.