Which of the following citations should come first on a works cited page?
a. talcott, richard. "great comets." astronomy. 2004. print.
b. lesko, leonard h. "pyramids." the world book encyclopedia. 2001. print.
c. brinkley, alan. the unfinished nation. new york: knopf, 1993. print.
d. carpenter, allan. facts about the cities. new york: wilson, 1992. print.