"Frequenz", 30.2 (1976): 25-48. Retrieved 22 May. 2013, from http://www.degruyter.com/view/j/freq.1976.30.2/issue-files/freq.1976.30.2.xml

Frequenz (1976), 30(2), pp. 25-48. Retrieved 22 May. 2013, from http://www.degruyter.com/view/j/freq.1976.30.2/issue-files/freq.1976.30.2.xml

Frequenz. 1976. 30(2): 25-48. Retrieved 22 May. 2013, from http://www.degruyter.com/view/j/freq.1976.30.2/issue-files/freq.1976.30.2.xml