APA
Heppner K., Evitts R., Postlethwaite J., Evitts R. & Postlethwaite J.. : .
Chicago
Heppner K.L, Evitts R.W, Postlethwaite J, Evitts R.W and Postlethwaite J.. : .
Harvard
Heppner K., Evitts R., Postlethwaite J., Evitts R. and Postlethwaite J.. : .
MLA
Heppner K.L, Evitts R.W, Postlethwaite J, Evitts R.W and Postlethwaite J.: . .