Παραπομπή APA

Perrin, R. (1971). Focus the future: An introduction to long range corporate planning. Management.

Παραπομπή Chicago Style

Perrin, Robert. Focus the Future: An Introduction to Long Range Corporate Planning. London: Management, 1971.

Παραπομπή MLA

Perrin, Robert. Focus the Future: An Introduction to Long Range Corporate Planning. Management, 1971.