 The first is the work of Feffer and Feffer and Gourevitch  , which related role taking ability to Piaget's theory of social decentering  and developed a projective test to assess children's ability to decenter as they mature.
<meaning-changed>  The first is the work of Feffer and Feffer and Gourevitch  , which related role taking ability to Piaget's theory of social decentering  and developed a projective test to assess children's ability to decenter as they mature.
 The first is the work of Feffer and Feffer and Gourevitch (1960) , which related role taking ability to Piaget's theory of social decentering and developed a projective test to assess children's ability to decenter as they mature.