Stockwell, R. P., Bowen, J. D., & Martin, J. W. (1965). The grammatical structures of english and spanish. The University Chicago Press.

Stockwell, Robert P., J. Donald Bowen, and John W. Martin. The Grammatical Structures of English and Spanish. Chicago: The University Chicago Press, 1965.

Stockwell, Robert P., et al. The Grammatical Structures of English and Spanish. The University Chicago Press, 1965.