APA
Barnum B. S., . (1979). Nursing theory. Boston: Little Brown and Company.
Chicago
Barnum Barbara Stevens, . 1979. Nursing theory. Boston: Little Brown and Company.
Harvard
Barnum B. S., . (1979). Nursing theory. Boston: Little Brown and Company.
MLA
Barnum Barbara Stevens, . Nursing theory. Boston: Little Brown and Company. 1979.