Understanding how to credit your sources using short in-text citations (or footnotes) can help you avoid plagiarism. Example:
The longer citation in your “References” or “Works Cited” list (at the end of your paper) includes, at least, the author, title, and source information. Example:
The next two paragraphs will help you with reading the parts of a citation and translating the parts into APA citation style format.
Here is the publication information for a book found in the Netherlands Central Catalogue (NCC):
APA-Format - as it would look in your “References” list:

Here is the publication information for a journal article retrieved online from the National Online Contents on 17 July, 2006:
APA Format - as it would look in your "References" list:
Note: for online articles you have to give information not just about the original journal where the article was published, but also what online database you got it from and when.