조국현. (2011). 독일어 교재 Schritte international과 Delfin의 워크북 분석. 외국어교육, 18(2), 365-386.
Cho, Kuk- Hyun. (2011). An analysis of the workbooks of the German language textbook ‘Schritte international’ and ‘Delfin’. Foreign Languages Education, 18(2), 365-386.