1. Should operations be regionalized?;Luft;N Engl J Med,1979
2. Regionalization of operations;Longmier;N Engl J Med,1979
3. Toward improving the outcome of pregnancy: recommendations for the regionaldevelopment of maternal and perinatal health services,1976
4. Rural perinatology;Hein;Pediatrics,1975
5. Evaluation of a rural perinatal care system;Hein;Pediatrics,1980