World Databases Series. Berlin, Boston: De Gruyter Saur, n.d.. Web. Retrieved 23 May. 2013, from http://www.degruyter.com/view/serial/36383

World Databases Series. (n.d.). Berlin, Boston: De Gruyter Saur. Retrieved 23 May. 2013, from http://www.degruyter.com/view/serial/36383

World Databases Series. n.d. Berlin, Boston: De Gruyter Saur. Retrieved 23 May. 2013, from http://www.degruyter.com/view/serial/36383