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Biology: Cite Sources

This guide has been designed to help you with information resources that you will use in your research. Select from the tabs above to search for all types of the books, journals, and websites.

Cite resources in METU Library

MLA Style and Formatting Guidelines

MLA is a format for citing sources and typing research papers in the humanities (English, literature, history, etc).

MLA recommends the following common rules when formatting your paper.  Use the MLA handbook to view the page number that follows the rule for further explanation. 

Be aware your professor may require slight changes to these rules.  Always verify with the professor on what format specifications to use for a particular assignment. 

Some common rules to follow are:

Title Page

Do not make a title page unless specified. Center your title on the line below the header with your name, and begin your paper immediately below the title.


Create a header that numbers all pages consecutively in the upper right-hand corner, one-half inch from the top and flush with the right margin. (Note: Your instructor or whoever is reading the manuscript may ask that you omit the number on your first page. Always follow their guidelines.)

First Page

Provide a double-spaced entry in the top left corner of the first page that lists your name, your instructor's name, the course, and the date.


Margins should be one(1)inch on all sides which includes top, bottom, left and right.(p. 132)

Font Preference and Size

Choose a standard, easy-to-read font and type size. For example, Times New Roman, 12 pt.(p. 132)

Line Spacing

The paper should be double spaced throughout the document.(p. 133)  

Page Numbering

Page numbers should be located in the upper right corner, one half inch from the top and flush with the right margin.  Type your last name before the page number unless otherwise specified by your professor. (p. 134)

Paragraph Indentation

Paragraphs should be indented 5 spaces or 1/2 inch.(p. 132)

Spacing after Punctuation

It is increasing common to use a single space after all punctuation marks.  However, two spaces is also acceptable.  Check with your professor to determine specification.


Overview of APA Style

APA Style is one of a number of sets of rules for writing used in the academic world, particularly in the areas of the health sciences, social sciences, psychology, education, and business.  The guidelines of the APA Style are developed and revised by the American Psychological Association (APA) in its Publication Manual of the American Psychological Association of which the sixth edition was published in the summer of 2009.  

Many students make the mistake of using APA Style only for their reference list.  APA Style covers all parts of writing and publishing--organization (title page, page numbering, margins, spacing, headings, etc.), punctuation, tables, in-text citations, the reference list, etc.  It even includes consideration of ethics in writing and bias in language.  APA Style is written primarily for publication of journal articles and does not always apply for papers written by undergraduate students.  If a faculty member requires APA style, it is best to determine the details of how he/she wants the style to be applied.