1. Perrott, Dorothy: Personal Communication.
2. Family Studies in Pittsburgh, Pennsylvania;Ciocco,1952
3. Sampling and Field Procedures of the Pittsburgh Morbidity Survey;Horvitz;Pub. Health Rep.,1952
4. An Epidemiologic Look at the Problem of Classification in the Field of Arthritis;Cobb;J. chron. Dis.,1955
5. Rosenbaum, J. R., and Cobb, S.: A Comparison of Data Obtained by Non-Medical Interviewers and Physicians on Pain, Morning Stiffness, and Joint Swelling. (To be published.)