Look at the periodicals.
A periodical is a publication that comes out periodically, like daily, weekly, monthly, quarterly, semi-annually, or bi-annually.
1) Decide which of the periodicals you have matches these categories
Trade or professional journal
How did you decide which kind it is?
What do you notice about academic journals?
Written by an academic, for an academic audience, published by an academic publisher or association, the authors' credentials are given, there is a works cited or reference list, and there are often footnotes or endnotes. Most are reporting on original scholarship, which could be a study or experiment.
A professor might suggest you use reference sources to gain background knowledge or a basic understanding of a topic. Notice the word REFER in the word "reference."
Some examples of reference sources are...
Professors often ask students to make sure to use "academic" sources for college assignments
In general, this means a source that is...
An electronic collection of materials which includes information describing each item that can be searched. Library databases search a specific set of information sources, especially periodicals.