APA

Petrarch F., Nichols J. G., . (2002). My secret book. London: Hesperus Press.

Chicago

Petrarch Francis, Nichols J G, . 2002. My secret book. London: Hesperus Press.

Harvard

Petrarch F., Nichols J. G., . (2002). My secret book. London: Hesperus Press.

MLA

Petrarch Francis, Nichols J G, . My secret book. London: Hesperus Press. 2002.