Verschuren, P. (1999). Designing a research project. Utrecht: Lemma BV.
Trích dẫn kiểu ChicagoVerschuren, Piet. Designing a Research Project. Utrecht: Lemma BV, 1999.
MLA引文Verschuren, Piet. Designing a Research Project. Utrecht: Lemma BV, 1999.
警告:這些引文格式不一定是100%准確.