Apart from printed material such as books and journals, source material from online resources should also be properly acknowledged in academic writing.

Mild cases of failure to acknowledge would be regarded as poor academic writing. Serious cases of failure to acknowledge, especially where there appears to be the intention to mislead the reader about the originality, would constitute plagiarism.

Examples of different citation styles are available at the website of the CUHK Library for reference.  Again the most important point about citing electronic source materials is not the format per se but the inclusion of all information necessary for identifying the source being cited. There is one important difference from printed works. The same web site (as identified by its URL) may change its contents from day to day; therefore the date of retrieval should always be included.