sack, K., & linsel, h. (1966). planning of technical progress in socialist countries: Planning of research and development. the institute of national planning.
Lua i Stíl Chicago (17ú heag.)sack, K., agus hermann linsel. Planning of Technical Progress in Socialist Countries: Planning of Research and Development. cairo: the institute of national planning, 1966.
Lua MLA (9ú heag.)sack, K., agus hermann linsel. Planning of Technical Progress in Socialist Countries: Planning of Research and Development. the institute of national planning, 1966.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.