Wasserman, P., & Paskar, J. (1974). Statistics sources: A subject guide to data on industrial, business, social, educational, financial, and other topics for the United States and internationally (4th ed.). Gale Research Co.

Wasserman, Paul, and Joanne Paskar. Statistics Sources: A Subject Guide to Data on Industrial, Business, Social, Educational, Financial, and Other Topics for the United States and Internationally. 4th ed. Detroit: Gale Research Co, 1974.

Wasserman, Paul, and Joanne Paskar. Statistics Sources: A Subject Guide to Data on Industrial, Business, Social, Educational, Financial, and Other Topics for the United States and Internationally. 4th ed. Gale Research Co, 1974.