Наші джерела

1. http://uk.wikipedia.org/wiki/%D0%9F%D0%BE%D0%B4%D1%96%D0%BB%D1%8C%D1%81%D1%8C%D0%BA%D1%96_%D0%A2%D0%BE%D0%B2%D1%82%D1

2. https://www.google.com.ua/#q=%D0%86%D0%B2%D0%B0%D0%BD%D0%BA%D0%BE%D0%B2%D0%B5%CC%81%D1%86%D1%8C%D0%BA%D0%B8%D0%B9+%D0%B7%D0%B0%D0%BA%D0%B0%CC%81%D0%B7%D0%BD%D0%B8%D0%BA+%E2%80%94+%D0%BB%D0%B0%D0%BD%D0%B4%D1%88%D0%B0%D1%84%D1%82%D0%BD%D0%B8%D0%B9+%D0%B7%D0%B0%D0%BA%D0%B0%D0%B7%D0%BD%D0%B8%D0%BA

3.http://zakon4.rada.gov.ua/laws/show/500-74-%D0%BF

4.http://uk.wikipedia.org/wiki/%D0%9F%D0%BE%D0%B4%D1%96%D0%BB%D1%8C%D1%81%D1%8C%D0%BA%D1%96_%D0%A2%D0%BE%D0%B2%D1%82%D1%80%D0%B8