APA

Jörnsten K., . (1979). Comparisions between pure gravity models and models where the distribution and locational benefits are variables. Linköping: Linköpings Universitet. Matematiska Institutionen. Rapport 1979:40.

Chicago

Jörnsten KO, . 1979. Comparisions between pure gravity models and models where the distribution and locational benefits are variables. Linköping: Linköpings Universitet. Matematiska Institutionen. Rapport 1979:40.

Harvard

Jörnsten K., . (1979). Comparisions between pure gravity models and models where the distribution and locational benefits are variables. Linköping: Linköpings Universitet. Matematiska Institutionen. Rapport 1979:40.

MLA

Jörnsten KO, . Comparisions between pure gravity models and models where the distribution and locational benefits are variables. Linköping: Linköpings Universitet. Matematiska Institutionen. Rapport 1979:40. 1979.