Membership shall consist of the incorporators and such natural persons as have been duly elected to membership and have paid the entrance fee as required by the bylaws, and have complied with such other requirements as the certificate of organization may contain, and successors-in-law to accounts of deceased members subject to individual approval by the board of directors. One entrance fee will be required for each account regardless of the number of joint owners. Other organizations (whether incorporated or not) composed primarily of the same individuals who are eligible to join the credit union are also eligible for membership. Credit unions shall be organized within groups which have a common bond of occupation, association, or residence; provided that one (1) corporate central credit union sponsored by the Mississippi Credit Union League may accept as members the credit unions that are members of the Mississippi Credit Union League and shall include in its title the words “corporate central”; and provided further that one (1) credit union sponsored by the Mississippi Credit Union League may accept as members the members of credit unions holding membership in the Mississippi Credit Union League, the members of their immediate families, the employees of the Mississippi Credit Union League and the members of their immediate families, organizations or associations of such persons, and other persons residing in this state who do not have the services of a credit union available to them, such credit union to be known as the Mississippi League Central Credit Union, subject to such limitations on membership as may be from time to time adopted by the board of directors in the minutes of the central credit union.