APA (7th ed.) Citation

Georgiev Venelin & Longdom Publishing. Functions, Principles and Problems of the Security System.

Chicago Style (17th ed.) Citation

Georgiev Venelin and Longdom Publishing. Functions, Principles and Problems of the Security System.

MLA (9th ed.) Citation

Georgiev Venelin and Longdom Publishing. Functions, Principles and Problems of the Security System.

Warning: These citations may not always be 100% accurate.