APA استشهاد

Williams, H. M. (1991). An essential english grammar with usage and composition. Calicut University.

استشهاد بنمط شيكاغو

Williams, H. M. An Essential English Grammar with Usage and Composition. Kozhikode: Calicut University, 1991.

MLA استشهاد

Williams, H. M. An Essential English Grammar with Usage and Composition. Calicut University, 1991.