with reference to sections 3, 4, and 14 (in so far as it relates to the aforementioned sections), 22, 23 and 25, means a natural person, or a group of two or more natural persons (whether acting in the furtherance of a common purpose or conspiracy or not), or a syndicate, gang, agency, trust, partnership, fund or other unincorporated association or organisation, or any incorporated association or organisation or other legal person, and includes, where appropriate, a cell, unit, section, subgroup or branch thereof or any combination thereof;