A reference is made up of some key details/elements about the source, that can broadly be broken down into the following:
Who has ‘made’ the item (the author, creator, compiler…)?
What is it called?
If part of a larger work, what is that called?
Where was (is) it disseminated/published?
Who is responsible for the dissemination / publishing?
When was it disseminated / published?
A direct quotation, or allusion, should always include the page number(s).
Often, once you have located the full reference listed on the references or bibliography list, you can normally identify the type of source by the information presented in the reference. Here are some tips for identifying some of the key types of source that you might come across on a reading/reference list:
Cooke, A. (2001) A guide to finding quality information on the Internet: selection and evaluation strategies. 2nd ed. London: Library Association Publishing.
Note the edition information, the publisher location (London) and publisher name (Library Association Publishing) which are included in the reference.
De Pinto, M., Jelacic, J., Edwards, W.T. (2008) Very-low-dose ketamine for the management of pain and sedation in the ICU. Acute pain [online], 10 (2), p. 100. Available at: doi:10.1016/j.acpain.2008.05.023 [Accessed 8 September 2008].
Note that the title of both the article ('Very low dose ketamine ... ') and the journal ('Acute pain') are included. The journal volume (10) and issue number (2) are also included.