Based on APA 6th ed., rule 6.03, p. 170, "when quoting, always provide the author, year, and specific page citation or paragraph number for non-paginated materials in the in text." To cite a specific part of a source, indicate the page, chapter, ... at the appropriate point in text." However, "when paraphrasing or referring to an idea contained in another work, you are encouraged to provide a page or paraphraph number, especially when it would help an interested reader locate the relevant passage in a long and complex text." (APA 6th ed. Rule 6.04, p. 171)