If a periodical includes a volume number, italicize it and then change to regular type and give the page range without "pp."
Example:34(1), 40-42.
If the periodical does not use volume numbers, include "pp." before the page numbers, so the reader will understand that the numbers refer to pagination.
Example:title, pp 40-42. Use "p." if the source is a page or less. Example: p. 1.
MLA
If periodical includes a volume number, write the volume number, then a period, then the issue number, and then give the page range without "pp."
Example: 34.1, 40-42.
If the periodical does not use volume numbers, include "pp." before the page numbers, so the reader will understand that the numbers refer to pagination.