Ph.D., Professor Emerita
University of Jyväskylä, Finland
Pitkänen, L. (1969). A descriptive model of aggression and nonaggression with applications to children's behaviour. Jyväskylä Studies in Education, Psychology and Social Research 19. Jyväskylä, Finland: University of Jyväskylä.
The book is out of print, but available as scanned in the following parts (pdf):
Preface, Contents, Introduction Part 1_a Part 1_b Part 1 summary Part 2_a Part 2_b Part 2_c Part 2 Summary, References, Appendices