1. A Secure Europe in a Better World-European Security Strategy, December 12, 2003, [Electronic resource]. - Available at: http://www.consilium.europa.eu/uedocs/cmsUpload/78367.pdf
2. Berlin Plus agreement [Electronic resource]. - Available at: http://www.europarl.europa.eu/meetdocs/2004_2009/documents/dv/berlinplus_/berlinplus_en.pdf
3. Cologne European Council Declaration on the common policy on security and defence (4 June 1999) [Electronic resource]. - Available at: http://www.cvce.eu/en/obj/cologne_european_council_declaration_on_the_common_policy_on_security_and_defence_4_june_1999-en-ee393bf3-d96f-46b8-8897-15546a0e1c0d.html
4. Consolidated Version of the Treaty on European Union, Article 21.2 [Electronic resource]. - Available at: http://eurlex.europa.eu/resource.html?uri=cellar:2bf140bf-a3f8-4ab2-b506-fd71826e6da6.0023.02/DOC_2&format=PDF
5. Lisbon Treaty. Article 42 [Electronic resource]. - Available at: http://www.lisbon-treaty.org/wcm/the-lisbon-treaty/treaty-on-european-unionand-comments/title-5-general-provisions-on-the-unions-external-action-andspecific-provisions/chapter-2-specific-provisions-on-the-common-foreign-andsecurity-policy/section-2-provisions-on-the-common-security-and-defencepolicy/129-article-42.html