Dr. Olshansky was countered by Samuel H. Preston , a professor of demography at the University of Pennsylvania .
Samuel H. Preston /business/person/company University of Pennsylvania
NNP NNP VBD VBN IN NNP NNP NNP , DT NN IN NN IN DT NNP IN NNP .
Samuel H. Preston
PERSON
University of Pennsylvania
ORGANIZATION
/business/person/company