BIBCYT http://bibcyt.ucla.edu.ve/cgi-win/be_alex.exe?Ultimo&Nombrebd=BIBCYT UCLA - Biblioteca de Ciencias y Tecnologia Felix Morales Bueno Toutenburg, H. P Principal Shalabh P Principal Heumann, C. P Principal Use of prior information in the form of interval constraints for the improved estimation of linear regression models with some missing responses p2430-2445, 16p