APA

sommerville i., . (1983). infomation unlimited. london: addison - wesley puplishing co.

Chicago

sommerville ian, . 1983. infomation unlimited. london: addison - wesley puplishing co.

Harvard

sommerville i., . (1983). infomation unlimited. london: addison - wesley puplishing co.

MLA

sommerville ian, . infomation unlimited. london: addison - wesley puplishing co. 1983.