@article{Heckhausen1987,
author = {Heckhausen, H. and Gollwitzer, P.M.},
title= {Thought Contents and Cognitive Functioning in Motivational versus Volitional States of Mind},
year = {1987},
doi = {10.1007/BF00992338},
journal = {Motivation and Emotion},
volume = {11},
number = {2},
pages = {101--120},
}