易发久. (2011). 每天进步一点点: Progress a little every day. 凤凰出版社.
Chicago (17e ed.) Bronvermelding易发久. 每天进步一点点: Progress a Little Every Day. 凤凰出版社, 2011.
MLA (8e ed.) Bronvermelding易发久. 每天进步一点点: Progress a Little Every Day. 凤凰出版社, 2011.
Let op: Deze citaties zijn niet altijd 100% accuraat.