An observational study of the request behavior of preschool children : developmental changes in the nature of requests as a function of the sex and status characteristics of peer targets
Internet
http://spectrum.library.concordia.ca/5674/1/NK61898.pdfElman, Meryl <http://spectrum.library.concordia.ca/view/creators/Elman=3AMeryl=3A=3A.html> (1984) An observational study of the request behavior of preschool children : developmental changes in the nature of requests as a function of the sex and status characteristics of peer targets. PhD thesis, Concordia University.