Abstract
Skillful citation requires both propriety of referencing format and effective incorporation of citations into one's own writing. This study analyzed the use of source materials in argumentative essays by two international students. The essays were written as Japanese reading course assignments. Results show that, although one student partially succeeded in integrating source information to support her own claims, the other failed to incorporate citations into her own arguments. Neither student was able to provide warrants for the concluding claim from sources appropriately. Neither was able to convey the meanings of the original texts correctly, which suggests a lack of sufficient reading comprehension proficiency.