"Frequenz", 18.1 (1964): 1-32. Retrieved 20 May. 2013, from http://www.degruyter.com/view/j/freq.1964.18.1/issue-files/freq.1964.18.1.xml

Frequenz (1964), 18(1), pp. 1-32. Retrieved 20 May. 2013, from http://www.degruyter.com/view/j/freq.1964.18.1/issue-files/freq.1964.18.1.xml

Frequenz. 1964. 18(1): 1-32. Retrieved 20 May. 2013, from http://www.degruyter.com/view/j/freq.1964.18.1/issue-files/freq.1964.18.1.xml