The issue number, and the comma which follows it, is never underlined. An issue number is only provided if the particular journal starts pagination over at page 1 at the beginning of each issue. However, if each issue's pagination begins with page 1, give the issue number in your reference entry. After the volume number, put a space, then the issue number in parentheses, then a comma. Neither the issue number, the space before it, or the comma after it is underlined.
Page numbers give the range of pages for the journal article.
The page numbers come directly after the comma that follows the volume or issue number, and are preceded by a space, separated by a hyphen, and followed by a period. After volume 18, 94-156. Title of journal article. Title of journal article. Morphological differences between American and Brazilian Pig Latin constructions.