No. 4 reprinted from Social security bulletin, February 1985, v. 48, no. 2
Physical description for original version: v. : 28 cm
原資料等に関する注記
原資料の出版事項: Washington, D.C. : U.S. Dept. of Health and Human Services, Social Security Administration, Office of Policy, Office of Research, Statistics, and International Policy, 1985-