References
- Gustafsson , Karl Erik . 1978 . “The Circulation Spiral and the Principle of Household Coverage,” . The Scandinavian Economic History Review , 26 (1) : 1 – 14 .
- Gustafsson , Karl Erik and Hadenius , Stig . 1976 . Swedish Press Policy. , Stockholm : The Swedish Institute .
- Porter , Michael E. 1980 . Competitive Strategy. , New York : Free Press .
- Seymore‐Ure , Colin . 1991 . The British Press and Broadcasting Since 1945. , London : Basil Blackwell .
- Veljanovski , Cento . 1990 . The Media in Britain Today. , London : News International .