Webb, E. J. (2000). Unobtrusive measures (Rev. ed.). Sage.
Chicago Style (17th ed.) CitationWebb, Eugene J. Unobtrusive Measures. Rev. ed. Thousand Oaks, Calif: Sage, 2000.
MLA引文Webb, Eugene J. Unobtrusive Measures. Rev. ed. Sage, 2000.
警告:這些引文格式不一定是100%准確.