Legal Examination of Choosing the Law Governing the Contracts by Cosignatories in International Private Law (Ø§ÙØªØ´Ø§Ø±Ø§Øª Ø¯Ø§ÙØ´Ú¯Ø§Ù ÙØ±Ø¯ÙØ³Û Ù Ø´ÙØ¯)