APA

Travers P. L., Shepard M., . (2016). Mary Poppins. Opens the Door: [novella]. London: HarperCollins Children's Books.

Chicago

Travers P L, Shepard M, . 2016. Mary Poppins. Opens the Door: [novella]. London: HarperCollins Children's Books.

Harvard

Travers P. L., Shepard M., . (2016). Mary Poppins. Opens the Door: [novella]. London: HarperCollins Children's Books.

MLA

Travers P L, Shepard M, . Mary Poppins. Opens the Door: [novella]. London: HarperCollins Children's Books. 2016.