The choice of source materials needs to be carefully considered taking a critical approach. In a thesis the sources should primarily be reliable and recent printed or electronic sources; like books, research reports and articles providing the latest information on one’s own field of study.
Moreover, other theses, patents, standards, product brochures, expert interviews and information given by authorities can be used as sources in a thesis. Sources that are vague and rapidly regenerated, such as opinions presented in online discussion forums or chatrooms, are not to be used. In addition, if one cannot reliably assess the expertise and qualifications of the author, one should not use the source in the thesis. It is advisable to search for information using several different databases or sources of information in order to find the best possible sources on the thesis topic.
In the thesis the sources used are referred to using the Harvard referencing style and its name-year system. Through this referencing system the reader can immediately see whose text is referred to, from what year the text is and the page number of the information. An in-text reference is a short reference to the detailed source information found in the list of references.
Whenever one refers to a text written by someone else, one must include a reference. The in-text reference written in brackets consists of the author’s last name and the year of publication, followed by a comma and the page number or the pages where the information is taken from. If the entire work is referred to, page numbers are not included. All electronic sources do not have page numbers and in that case, page numbers also are not included in the reference.
Usually the source text is paraphrased in the thesis, i.e. the writer of the thesis rewrites the information in his/ her own words and the in-text reference follows immediately. It must be evident for the reader exactly which part of the text is based on a source. The placement of the full stop in the in-text reference indicates which part of the text is based on a source.