Title Page: The title page is the page that contains the title of the book, the author (or authors) and the publisher.

Does the page list the publisher?

The name of the publisher can be found on the title page and some times on the copyright page.

Is it true that in a reference with more than 20 authors separate the listing of the first 19 authors with the last author with an ampersand?

List by last names and initials; commas separate author names. After the first 19 authors' names, use an ellipsis in place of the remaining author names. Then, end with the final author's name (do not place an ampersand before it). There should be no more than twenty names in the citation in total.