"This measure prohibits the calling of a strike by a labor organization in any business or plant or unit thereof, except when authorized by the vote of the majority of all members of the organization employed in the business, plant, or unit thereof. Such authorization is to be expressed by a secret written or printed ballot at a meeting called for that purpose. The Labor Relations Commission is authorized to make the rules for the conduct of voting. Within twenty-four hours after the voting the labor organization conducting it shall make a written report of the result of the commission, which shall be a permanent public record. If no report is filed the vote taken shall be void and a person making a false report shall be guilty of perjury. Coercion and intimidation of members of a labor organization in connection with such voting is made a penal offense."
Source for Popular Vote data: Massachusetts Secretary of State. Election Statistics, 1948, Massachusetts Secretary of State (archive.org/details/electionstatisti19461948mass) (accessed 15 Apr 2012)