@article{ref1,
title="Verbal interactions: mothers and their retarded children vs mothers and their nonretarded children",
journal="American journal of mental deficiency",
year="1973",
author="Marshall, N. R. and Hegrenes, J. R. and Goldstein, S.",
volume="77",
number="4",
pages="415-419",
abstract="<p>[Abstract unavailable]</p><p>Language: en</p>",
language="en",
issn="0002-9351",
doi="",
url="http://dx.doi.org/"
}