When you write a report, an essay or other assignment you will most often need to support your arguments by referring to other published work such as academic journal articles, books, newspaper articles, government reports, dissertations and theses, and material from the Internet. You will need to give accurate references:
All references cited should be included in the reference list and all references included in the bibliography must be cited in the text.
Citations in the text could be written in many ways, the two most common in science are the Harvard style, where name(s) of the author(s) and the year of publication are written in the text and the Vancouver style, where each individual source has its own number which then could be found in the reference list.
The Harvard style is the most common way of referencing in biology, for example:
Persson (1985) remarked that the zebra is a striped animal, the stripes will never disappear.
The zebra is a striped animal, the stripes will never disappear (Persson, 1985).
If the source has two authors it should be cited as Smith and Persson (1987) and if there are more than two authors you should write Smith et al. (2001), et al. is latin and stands for et alli which means "and others". In the reference list, however, all names of the authors must be given, in the order of appearance!!
A reference list could be shaped in a number of ways. Every academic journal has its own style. In the reference list the references should be arranged in alphabetical order of the publication's first author’s last name. If the same author is represented with more than one publication, arrange them in chronological order. If an author has two or more publications from the same year, use small letters, 1999a, 1999b to separate them. Some styles demand abbreviated forms of journal titles while other demand the full titles, see links below for "approved" abbreviations.