Hopkinson, Alan (Ed.). "1. INTRODUCTION" UNIMARC Manual. Berlin, Boston: Walter de Gruyter – K. G. Saur, 2008. 7-9. Web. Retrieved 22 May. 2013, from http://www.degruyter.com/view/books/9783598441196/9783598441196.7/9783598441196.7.xml

1. INTRODUCTION (2008). UNIMARC Manual (pp. 7-9). Berlin, Boston: Walter de Gruyter – K. G. Saur. Retrieved 22 May. 2013, from http://www.degruyter.com/view/books/9783598441196/9783598441196.7/9783598441196.7.xml

Hopkinson, Alan (Ed.). 2008. 1. INTRODUCTION. In UNIMARC Manual, 7-9. Berlin, Boston: Walter de Gruyter – K. G. Saur. Retrieved 22 May. 2013, from http://www.degruyter.com/view/books/9783598441196/9783598441196.7/9783598441196.7.xml