820 ILCS 140/4

(820 ILCS 140/4) (from Ch. 48, par. 8d)

Sec. 4.

Before operating on the first day of the week, which is commonly
known as Sunday, every employer shall post in a conspicuous place on the
premises, a schedule containing a list of his employees who are required
or allowed to work on Sunday, and designating the day of rest for each.
Anything in this Act to the contrary notwithstanding, no employee shall
be required to work on the day of rest so
designated for him.

(Source: P.A. 80-1294.)