Effective research is done with the help of appropriate literature search tools. To do this, you need to have an idea of the type(s) of document(s) you want or the type of documents that might contain the information you want.
There are several ways to classify information sources.
Here is how to differentiate between primary, secondary and tertiary sources (George Mason University, 2014).
| Source type | Definition | Examples in engineering |
| Primary sources | Primary sources are original documents produced during the research process. |
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| Secondary sources | Secondary sources are analytical documents that interpret primary sources. They provide an intermediate point of view between primary sources and readers. They help contextualize, synthesize, evaluate and analyze the information found in primary sources. |
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| Tertiary sources | Tertiary sources are documents that aim to synthesize a large amount of knowledge from primary and secondary sources. They offer a digested version of the information, either for the general public or for professionals in specific fields. |
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Grey literature refers to sources disseminated outside of commercial channels. Some materials are not listed in traditional library documentary resources, but are still essential. These documents include:
Our translation from Schöpfel, J. (2015).
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George Mason University. (2014). Primary, Secondary, & Tertiary Sources. Repéré à https://collegeresearch.gmu.edu/primary-secondary-tertiary/
Schöpfel, J. (2015). Littérature « grise » : de l’ombre à la lumière. I2D - Information, données & documents, 52, 28-29. https://doi.org/10.3917/i2d.151.0028