Walls, H. B. (1974). Data collection systems: National dual record and related systems. International Program of Laboratories for Population Statistics.
Chicago Style (17th ed.) CitationWalls, H Bradley. Data Collection Systems: National Dual Record and Related Systems. Chapel Hill, N.C: International Program of Laboratories for Population Statistics, 1974.
MLA (9th ed.) CitationWalls, H Bradley. Data Collection Systems: National Dual Record and Related Systems. International Program of Laboratories for Population Statistics, 1974.