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Influential developmental psychologists from the 20th century include Urie Bronfenbrenner , Erik Erikson , Sigmund Freud , Jean Piaget , Barbara Rogoff , Esther Thelen , and Lev Vygotsky .
 Urie Bronfenbrenner, Erik Erikson, Sigmund Freud, Jean Piaget, Barbara Rogoff, Esther Thelen, Lev Vygotsky
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Text: {0} 
Answer:
 Urie Bronfenbrenner, Erik Erikson, Sigmund Freud, Jean Piaget, Barbara Rogoff, Esther Thelen, Lev Vygotsky