looseleaf service.A type of lawbook having pages that are periodically replaced with updated

pages, designed to cope with constant change and increasing bulk.

“The first loose leaf service covered the federal income tax, and was published in 1913 shortly after the Federal Income Tax Law of 1913 went into effect. It was followed in 1914 by a service reporting on the activities of the Federal Trade Commission, which had just been established. The loose leaf method was, therefore, first used as a means of reporting new tax and business laws which were to be subject to administrative interpretation …. These first loose leaf services were designed … not to reprint just the bare text of the revenue and commission acts, but to follow up and report each new development on these new laws as it occurred.” Arthur Sydney Beardsley, Legal Bibliography and the Use of Law Books § 185, at 313–314 (1937).
[Blacks Law 8th]