对于留学生而言，在写论文或者综述的时候，都会有参考的论文系统格式。一般学校或者导师都会指定使用某种格式,比如常见的哈佛格式，芝加哥格式，APA格式、MLA格式等等。尽管如此，我们依然有必要了解一些常用的写作格式以及不同格式的注意事项。本文主要以哈佛系统格式为基础，让您了解不同格式的关键要素。

When composing any piece of written academic work – be it an essay, dissertation or review – it is important to reference secondary sources clearly. There are several methods by which you may do this, though the choice may be made for you: some publications specify how their work must be acknowledged, and indeed some universities or faculties specify which system students must use. Nonetheless, it can still be helpful to have some insight into all major referencing systems. This guide is the first in a series that will explain the key elements of every referencing system, and how you might adopt each one.

But first, let’s take a look at what a referencing system is, in its essence, and why you should use one.

What are the different referencing systems?

Unfortunately there is no ‘universal’ system for referencing (wouldn’t that be nice and simple!) Instead, most scholars adopt one of the following (currently the most commonly-used systems in American and the UK):

1. The Harvard System (sometimes known as the ‘Author Date’ system)
2. Chicago System
3. American Psychological Association (APA)
4. Modern Language Association of America (MLA)
5. Modern Humanities Research Association (MHRA)

In recent years there has been a trend toward systems like Harvard (‘Author Date’), which features short citations within the text (in parenthesis) – as opposed to systems which favour footnote (full references to sources at the bottom of the page) or endnotes (full references at the end of the work). However, it does tend to vary from subject to subject and institution to institution.

Why should I use a referencing system when writing essays?

It is crucial to acknowledge when you are drawing on another author’s text or academic ideas. Not only does this enhance your authority when discussing your chosen subject – you have clearly done your research – it also ensures that there can be no suggestion that you may be plagiarising another’s ideas.

Which details do I need in order to reference correctly?

Though it may not be an obvious part of the writing process itself, careful collation of references will enhance your essay writing skills in general: it should be a box that you always tick as you go along, rather than something that you scramble to do after the event.

As a rule of thumb, we recommend having a separate sheet of paper handy at all times when writing or researching your essay, and noting down the following details clearly as you go:

1. The author’s name (or the editor’s).
2. The edition (if not the first).
3. The year the work was published and where it was published (city).
4. The title of the work.
5. The name of the publisher.
6. If it’s an article, include the title of the article; the page number(s); and any other pertinent information (such as the volume number).
7. If it’s an electronic resource, include the date the source was accessed and the electronic address.
8. If you are quoting directly from the source, don’t forget to include a page number.