I want to create website for association. Please recommend me CMS with its module which could meet my requirements. Requirements: • Various membership (free and paid); • Various groups for joining (free and paid); • Member could be member of some groups simultaneously(free and paid groups); • Multilingual (English, Russian, French) ; • Paid Registration for take part in congresses, conferences and seminars; • Online sending abstracts and scientific works to administrator by members for congress. approval and comments them by administrator; • Association can sells books, magazines and subscription from mini shopping cart of the website; • Payment method must be credit Cards and Manual (bank transfer); What CMS with its module do you recommend? P.S. What website also I can post my request, what do you recommend?