In assignments, sources are referred to by the  name of the author and the date of publication (the Harvard reference system), or by a number (the Vancouver reference system). References using the numerical Vancouver system often place the number within brackets.

About 82% of references in the Physical Sciences assignments follow the numerical Vancouver system. The rest follow the Harvard system.

When using the Vancouver system you do not necessarily name the authors of your source. In these examples the authors are not named:

The relative efficiency is defined as the ratio of the photopeak flux to the total flux recorded [3].

Source [4] is recommended as a brief introduction to Scan.

In this example the authors are named:

Middleton and Sivaswamy suggest that hexagonal sampling exploit the oblique effect in human vision thereby providing a better image when viewed by humans [4].

Harvard references can be ‘integral’ or ‘non-integral’.

In integral references the author’s name (or an equivalent proper noun) is part of the sentence. For example:

Levitt and Lawton (1990) posited three basic questions that define robot mapping and navigation.


As Trotman-Dickenson (1996) explains on page 406, there were three different methods to encourage public transport to and from the airport.

In non-integral references proper names and dates are provided within brackets. For example:

The ratio of specific heat at constant pressure to the specific heat at constant volume was measured using a variation on the Rüchardt method (Rüchardt 1929).

For every million words in the Physical Sciences assignments there are about 17 integral citations and 32 non-integral citations.

Ibid and op. cit. do not occur in the Physical Sciences assignments.

Reporting Verbs

Here are some verbs typically used for reporting other people's work in Physical Sciences.

Reporting Verbs in Physical Sciences. Examples



I think the website looks really useful and intend to use it in several ways. Today I showed my class the website page on use of references for the physical sciences discipline.

They were also very interested in the examples of reporting verbs used in their discipline.

Does the search method identify only Harvard style in text citations, or also other referencing systems such as [1] which would then have [1] in the reference list with the details of the book?

Dear Peter
Thanks for your positive comments about the site, and for your interesting question.
The Vancouver "author-number" system is quite popular in the Physical Sciences, although it does not seem to be as common as the Harvard system. 
In the bibliography sections of the BAWE corpus I found:

  • 269 numbered references in the Physical Sciences (44.3 per million words)
  • 222 numbered references in the Life Sciences (26.6 per million words)
  • 189 numbered references in the Social Sciences  (22.7 per million words) 
  •  27 numbered references in the Arts and Humanities (3.2 per million words).

I think we'll add some more information about this on the site soon!
The Writing for a Purpose Team