1. How do I cite two or more authors?
When there are two or more authors for a reference, you should only use the first author's family name in the in-text reference followed by the abbreviation "et al.". For a non-integral reference, only include the reference number in square brackets. For example:
- According to Choi et al. , students in Asia are more studious than their North American counterparts.
- Wong et al.  strongly support the use of technology in the classroom.
- Asian students devoted on average 16 hours per week to out-of-class study compared to 10 hours for North American students .
2. In the reference list what should I do when there is many authors?
If there are more than two authors:
List by last names and initials. Separate names by a comma after the initials.
||Chow RK, Ping SM. Mood management in university students. J. of
Asian Psychology. 2004;45(3):1034-1048.
||Luk WK, Chan YK, Sing AN, Burton H, Heart L, Burns HU. The Chinese student: A study. J. of East Asian Psychology. 2009;32(5):1190-1204.
If there are many authors:
Give all authors, regardless of the number.
||Tukker A, Emmert S, Charter M, Vezzoli C, Stive E, Andersen MM, Chan ER. Fostering
change to sustainable consumption and production: An evidence based view. J. of
Cleaner Production. 2011;16:1218-1225.
3. How do I cite when there is no author and/or no date?
When no person is mentioned, include the title of the source or the authoring/sponsoring organisation in place of the author.
- The English Language Centre  aims to improve students' communication skills to enable them to attain excellent results in their academic and professional lives.
When no date of publication is given but the publication contains a date of copyright, use the date of copyright preceded by the letter "c"; for example c2012. If neither a date of publication nor a date of copyright can be found, but a date can be estimated, insert a question mark after the estimated date and place date information in square brackets. If the date of publication cannot be estimated, use [date unknown].
 Amano Y. Final fantasy: 20th anniversary artbook. Macau: ACG Studio; [date unknown].
 Equal Opportunities Commission. Equal treatment for native speakers.
Hong Kong: Equal Opportunities Commission; [2001?].
However, be cautious about using sources without dates. A source with no date might not be reliable.
4. How do I present exact quotations?
Short quotations of fewer than thirty words should be enclosed in double quotation marks (" ... ") and be accompanied by an in-text reference. Remember to include the page or paragraph number after the reference number in square brackets and in the reference list so that the reader can find the quotation.
- Research by Leung [10:15] indicates that "students in Hong Kong devote on average 5 hours a week to their English studies from the age of four".
Longer quotations of more than thirty words should be presented without quotation marks and indented (using Tab key) at the left. Include the page or paragraph number in the complete reference list.
According to Obama [11:45], America:
should be more modest in our belief that we can impose democracy on a country through military force. In the past, it has been movements for freedom from within tyrannical regimes that have led to flourishing democracies; movements that continue today. This does not mean abandoning our values and ideals; wherever we can, it’s in our interest to help foster democracy through the diplomatic and economic resources at our disposal.
5. Where exactly do I put the full stop when quoting and/or citing?
Full stops must always be placed at the very end of a sentence, after the quotation and/or in-text reference. For example:
- According to Mooney [12:34], "exam pressure in Hong Kong has lessened slightly in the past decade".
- Research indicates that students in Hong Kong have had four mobile devices before their 18th birthday .
6. Can I cite two or more sources at the same time?
Yes you can. Study the following examples.
Example 1: ... as shown by Chan , ;
Example 2: ... as mentioned earlier , –, ;
Example 3: ... Wong  and Brown and Jones ;
In example 1, Chan has at least two articles in the reference list. In example 2, there are six references mentioned. In example 3, there are two integral references.
7. Can I paste the URL of a webpage into my essay as an in-text citation?
No. Follow the Vancouver referencing conventions for all sources. If you are unsure how to reference a website because there is no author or date information, follow the guidelines provided below for referencing sources without authors or dates.
8. How do I cite information from one author (Author 1) which I have found in a book or journal article by another author (Author 2)?
This is secondary citation. Vancouver style does not allow for the use of secondary sources in in-text citations. You should try to locate the original source of information which is cited in a work which you have read. If an original source cannot be located, you should cite it as following in the reference list.
||Cooper M. Relapse and craving: A commentary. Alcohol Alert. 1989;6:3. Cited by Hull BT, Kline C, Tulper KE. Alcohol and degeneration. J. East Asian Medicine. 2008;6(3):761-7.