It's the only bargain in textbook shopping this semester: students buying sourcebooks for their spring classes get an arithmetic lesson for free. Prices have skyrocketed due to increased enforcement of copyright laws, according to sourcebook publishers.

Norman L. Shapiro, one maker of University sourcebooks, said he was forced to increase prices after he received a letter from the director of copyright education of the Association of American Publishers, Inc. (AAP) as well as a visit from AAP representatives.

Now, sourcebook prices at Shapiro's Gnomon Copy Center on 99 Mt. Auburn Street will reflect the cost of all copyright fees associated with the material contained in the sourcebooks he publishes.

"Under the law, one must pay the publisher a royalty on copyrighted material," he said.

In her letter to Shapiro, Director of Copyright Education Jill M. Braaten wrote: "Compliance with copyright law continues to be an important responsibility for the campus community."

A copyright notice is now issued with every sourcebook Shapiro produces. "The reproduction of this material was copied with permission of the copyright holder," the disclaimer reads. "In an educational setting it is especially necessary to operate within the bounds of the copyright laws."

The result? A 1000-page sourcebook which previously sold for about $50 now sells upwards of $130, Shapiro said. On a single sourcebook page, containing two pages of copy- righted material, "what used to be a nickel isnow 13-21 cents, and it all goes to thepublisher," he added.

William G. Witt, the copyright officer forsourcebook publications for the Faculty of Artsand Sciences at Harvard, gave another example of ahighly-priced sourcebook.

"I can guarantee you that in a couple of daysthe Historical Studies A 12 sourcebook will be inthe Science Center, and it will be the mostexpensive sourcebook we've ever produced," Wittsaid.

That sourcebook will cost $138-50. Witt saidthat one of the reasons for the price increase isthe sheer size of the book, the biggest evercomplied.

The other reason, he said, is the addedcopyright fees. Each publisher charger up to $7for a publication, said Witt, and With 77selections in the Historical Studies A-12sourcebook, those fees will account for themajority of new costs.

Witt added that publishers are increasingprices not only every year, but every semester aswell. In 1992, he said, a particular publishercharged $200 for a selection. Now that publisheris charging $800.

Shapiro said that, as a result of complyingfully with the law, "I do not have anywhere nearthe amount of packets that I could have had."

The Harvard Coop has also adapted to the morestringent enforcement of the copyright laws.Sourcebooks sold at Coop now include a messagesaying that the Coop's Custom Publishing unit has"paid all proper royalties for all materialsenclosed.