"Frequenz", 12.8 (1958): 241-272. Retrieved 19 May. 2013, from http://www.degruyter.com/view/j/freq.1958.12.8/issue-files/freq.1958.12.8.xml

Frequenz (1958), 12(8), pp. 241-272. Retrieved 19 May. 2013, from http://www.degruyter.com/view/j/freq.1958.12.8/issue-files/freq.1958.12.8.xml

Frequenz. 1958. 12(8): 241-272. Retrieved 19 May. 2013, from http://www.degruyter.com/view/j/freq.1958.12.8/issue-files/freq.1958.12.8.xml