Rodríguez Rudas, F. (1995). Language as a System and the Process of Word Acquisition and Formation Throughout the Development of the English Language up to the Twentieth Century. Panamá: : Universidad.

Rodríguez Rudas, Francisco. Language As a System and the Process of Word Acquisition and Formation Throughout the Development of the English Language Up to the Twentieth Century. Panamá: : Universidad, 1995.

Rodríguez Rudas, Francisco. Language As a System and the Process of Word Acquisition and Formation Throughout the Development of the English Language Up to the Twentieth Century. Panamá: : Universidad, 1995.