APA (7th ed.) Citation

Sommers, F., & Englebretsen, G. (2000). An invitation to formal reasoning: The logic of terms. Ashgate.

Chicago Style (17th ed.) Citation

Sommers, Fred, and George Englebretsen. An Invitation to Formal Reasoning: The Logic of Terms. Aldershot [u.a.]: Ashgate, 2000.

MLA (9th ed.) Citation

Sommers, Fred, and George Englebretsen. An Invitation to Formal Reasoning: The Logic of Terms. Ashgate, 2000.