This study takes a multidimensional approach to citation analysis, examining citations in multiple subfields of engineering, from both scholarly journals and doctoral dissertations. The three major goals of the study are to determine whether there are differences between citations drawn from dissertations and those drawn from journal articles; to test a methodology incorporating both internal and external citation sources; and to explore the citation habits of researchers in science, technology, engineering, and mathematics (STEM) subfields. The results reveal variations in how STEM subfields conduct research in career and academic settings and are more nuanced than internal or external citation data alone can provide. The results have practical collection development implications.