APA
LearningExpress (Organization), . (2008). Office correspondence made easy. New York: LearningExpress.
Chicago
LearningExpress (Organization), . 2008. Office correspondence made easy. New York: LearningExpress.
Harvard
LearningExpress (Organization), . (2008). Office correspondence made easy. New York: LearningExpress.
MLA
LearningExpress (Organization), . Office correspondence made easy. New York: LearningExpress. 2008.