Documenting your sources
In your lab reports you will typically use information from sources such as your textbook, lab manual, a reference book, and articles published in a science or engineering journal. When you use information from sources, you need to tell the readers where the information came from and where the readers can locate the sources. This is what citations and references are for.
A citation tells the readers where the information came from. In your writing, you cite or refer to the source of information.
A reference gives the readers details about the source so that they have a good understanding of what kind of source it is and could find the source themselves if necessary. The references are typically listed at the end of the lab report.
There are many different forms of documentation (systems of citation and reference), varying across academic fields. You may be familiar with MLA (Modern Language Association) used in English. But even within academic fields there are different forms because different scholarly journals specify a system to be used in those journals.
Smart advice: Find out what form of documentation is appropriate to use in your class before you write your first report. The best place to look is the lab manual. If you don't see the form of documentation given there, then ask the lab instructor or the professor of the lecture section.
More smart advice: If you can't find out from the lab manual or the teacher what form of documentation you should use, or if you are told to choose one on your own, find out what scholarly journal is appropriate to the field you are studying and use it as a guide to documentation. Find a recent copy of journal in the library or online. It will say what form that it uses (in the "guide to authors"). But you can also determine what to do by looking at how the citations and references are done in an article in the journal.
Generally speaking, there are three basic systems of documentation in science and engineering: the name-and-year system, the alphabet-number system, and the citation-order system. If your teacher says to use one of these systems, you can use the following brief descriptions to guide you in documenting sources:
The Name-and-year system
Citations: When you cite the source of information in the report, you give the names of the authors and the date of publication.
Jenkins and Busher (1979) report that beavers eat several kinds of herbaceous plants as well as the leaves, twigs, and bark of most species of woody plants that grow near water.
Beavers have been shown to be discriminate eaters of hardwoods (Crawford, Hooper, and Harlow 1976).
References: The sources are listed at the end of the report in alphabetical order according to the last name of the first author, as in the following book and article.
Crawford, H.S., R.G. Hooper, and R.F Harlow. 1976. Woody Plants Selected by Beavers in the Appalachian and Valley Province. Upper Darby, PA: U.S. Department of Agriculture.
Jenkins, S.H., and P.E. Busher. 1979. Castor canadensis. Mammalian Species. 120:1-8.
The Alphabet-number system
Citations: When you cite the source of information in the report, you give a number in parentheses that corresponds to the number of the source in the alphabetical listing in the "References."
Jenkins and Busher report that beavers eat several kinds of herbaceous plants as well as the leaves, twigs, and bark of most species of woody plants that grow near water (4).
Beavers have been shown to be discriminate eaters of hardwoods (3).
References: The sources are listed in alphabetical order and numbered accordingly, as in the following book and article.
- Crawford, H.S., R.G. Hooper, and R.F Harlow. 1976. Woody Plants Selected by Beavers in the Appalachian and Valley Province. Upper Darby, PA: U.S. Department of Agriculture.
- Jenkins, S.H., and P.E. Busher. 1979. Castor canadensis. Mammalian Species. 120:1-8.
The Citation-Order System (typically used in engineering--IEEE documentation)
Citations: When you cite the sources of information in the report, you give a number in brackets that corresponds to the number of the source listed in the order in which they appear in the report, the source listed first as [1], the next source [2], etc.
Jenkins and Busher report that beavers eat several kinds of herbaceous plants as well as the leaves, twigs, and bark of most species of woody plants that grow near water [1].
Beavers have been shown to be discriminate eaters of hardwoods [2].
References: The sources are listed in the order in which they are cited in the report, as in the following book and article.
- S.H. Jenkins and P.E. Busher, "Castor canadensis,"Mammalian Species. Vol. 20, Jan. 1979.
- H.S. Crawford, R.G. Hooper, and R.F Harlow, Woody Plants Selected by Beavers in the Appalachian and Valley Province. Upper Darby, PA: U.S. Department of Agriculture, 1976.