Classical works (e.g. religious texts; ancient Greek & Roman writings) are typically only cited in-text and not in the reference list.
Sometimes an author will refer to another author's research. If the original source is relevant to your research, then you should make every effort to find it and read it. If this is not possible, then the in-text citation should include both the source that you have read and the source that you have not read, but only the source that you have actually read should be included in the references.
(Author Surname, as cited in Author Surname [of the source you read], Year)
(as cited in Author Surname [of the source you read], Year)
Author, A. A [of the source you read]. (Year). Book title: Subtitle. Place of Publication: Publisher.
The mastery of APA increases an author's chance of scoring well on an assignment (Culver, as cited in Jones, 2009).
According to Culver (as cited in Jones, 2009), learning APA "can be tough, but like any skill, it just takes practice" (p. 23).
Note: Cite only the secondary source [the source you read] in the reference list.
Jones, J. (2009). Scholarly writing tips. Minneapolis, MN: Publishing House.
...applies to the building subsurface (BC Office of Housing and Construction Standards, 2012).
BC Office of Housing and Construction Standards. (2012). BC Building Code (Division B, subsection 4.2.2). Retrieved from http://www.bccodes.ca.