A digital object identifier (DOI) is a unique code assigned to an electronic publication so that it may be located on the Internet through a persistent link. It is recommended by the APA that when a DOI is available, it be included for both print and electronic publications. If a DOI is included, no additional Internet retrieval information is necessary.
Not all publications have a DOI, but you can look up an article on the CrossRef web site to find the correct DOI to include in a reference:
In general, only the first letter of the article title and subtitle are capitalized, with the exception of proper nouns.
The first letter of every significant word in the journal, magazine or newspaper title is capitalized, with the exception of articles and prepositions, such as an, the, of, in, etc.
The volume number for journals is always italicized. The issue number is provided in brackets after the volume number only if the journal is paginated by issue. If available, both volume and issue numbers are included in references to magazine articles. References to newspaper articles do not include volume and issue numbers, even if they are given.
Information required for an article referencce includes:
Examples of References:
One Author (Journal Paginated by Issue):
Critchley, T. (2008). The rainforests on our doorstep. Ecologist, 38(1), 38-42.
More than Seven Authors (Journal Paginated by Volume):
Note: If an article has more than seven authors, list the first six authors followed by an ellipsis ( . . . ) and the last author's name.
Botkin, D. B., Saxe, H., Araujo, M. B., Betts, R., Bradshaw, R. H. W., Cedhagen, T., . . . Stockwell, D. R. B. (2007). Forecasting the effects of global warming on biodiversity. Bioscience, 57, 227-236. doi:10.1641/B570306
Vogel, J. M., & Lazar, B. (2010, July/August). Global cooling: Science and myth. Weatherwise, 63(4), 24-31.
Newspaper Article (No Author's Name Provided):
Note: If there is no author's name provided, begin the reference with the article title followed by the date. In-text citations should include a shortened form of the title in quotation marks followed by the date (see below). All significant words in the shortened title in the parenthetical citation should be capitalized.
Maple trees endangered, watchdog says. (2012, January 11). The Toronto Star, p. A7.
Examples of In-Text Citations:
According to Botkin et al. (2007), there is no reliable way to forecast rates of extinction.
Global cooling can be seen as the result of natural cycles, whereas "climate warming" may be caused by the accumulation of greenhouse gases in the atmosphere due to human acitivity, such as industrial pollution and land use (Vogel & Lazar, 2010).
The destruction of maple trees due to the double threat of long-horned beetles and global warming would have financial repercussions, specifically for "tourism, forestry and the $15 million annual maple syrup industry" ("Maple Trees," 2012, p. A7).