APA

Butterworth R., Flodin M., . (1989). Signing made easy: a complete program for learning language, includes sentence drills and exercises for increased comprehension and signing skill. New York, NY: Perigee Books.

Chicago

Butterworth Rod, Flodin Mickey, . 1989. Signing made easy: a complete program for learning language, includes sentence drills and exercises for increased comprehension and signing skill. New York, NY: Perigee Books.

Harvard

Butterworth R., Flodin M., . (1989). Signing made easy: a complete program for learning language, includes sentence drills and exercises for increased comprehension and signing skill. New York, NY: Perigee Books.

MLA

Butterworth Rod, Flodin Mickey, . Signing made easy: a complete program for learning language, includes sentence drills and exercises for increased comprehension and signing skill. New York, NY: Perigee Books. 1989.