(70 ILCS 1505/7.1) (from Ch. 105, par. 333.7a)
    Sec. 7.1. Except where the equipment does not burn or consume Illinois coal as efficiently as other coal, the Chicago Park District shall comply with the provisions of "An Act concerning the use of Illinois mined coal in certain plants and institutions", filed July 13, 1937, as heretofore or hereafter amended.
(Source: Laws 1951, p. 1746.)