Employee organizations shall be prohibited:from calling, maintaining, or participating in a strike; or from inducing, encouraging, aiding, or abetting any employee to:engage in a strike; withhold his services as such employee; picket in furtherance of either of the aforesaid purposes in front of, about, or in close proximity to any of the school buildings operated and maintained by the School Board; or picket for any purpose in front of, about, or in close proximity to any school building while school is in session or during such period prior to and following such session, as may be prescribed by the School Board. If a certified employee organization shall violate any of the provisions herein, its certification shall immediately be revoked by the School Board, and said employee organization and any other employee organization which violates any of the provisions herein shall be ineligible to participate in or be considered for election as exclusive representative for a period of 2 years thereafter. Provided, however, that nothing contained in this subsection shall in any way limit the City in seeking any other legal remedies to prevent or prohibit such illegal conduct. City Code, 1976/83, art. 24, §18(g) Ord. 67-1031