The Dean of the Faculty yesterday distributed a memorandum warning professors to comply with U.S. copyright laws when sending spring reading lists to undergraduate libraries.

The memo, signed by Dean A. Michael Spence, is part of a larger effort within the University to assure conformity with seven-year-old laws that restrict photocopying of published material.

Lamont, Hilles and Cabot libraries, which carry all required reading for undergraduate courses, must follow a complicated procedure when a professor asks that photocopied excerpts of books be placed on reserve.

To reproduce material less than 1000 words long, one needs permission from the individual copyright holder. This process, which can take Harvard libraries up to two months, is necessary for about 100 of each semester's readings, said Alan A. Lanham '70, assistant librarian at Lamont.

Colleges across the country have in tensified efforts to comply with the so called "Copyright: Law" since the Association of American Publishers filed a multi-million dollar lawsuit against New York University two years ago.

That suit, one of four filed by the trade association, was settled out of court, but Harvard's attorneys "`have over' time been working with the libraries" to meet the often-uncertain standards set by the law, Martin Michaelson, deputy general counsel, yesterday.

Spence issues the memo at the request of the fluce libraies, marking the clean office first effort the sappon compliance with the law.

"We asked them for help," said Cabot Librarian Alan F. Erickson, who added that "it's a little bit easier to follow the copyright procedures now" than when the laws first appeared.

Occasionally authors refuse permission to have their works copied, which could deprive them of royalties from book sales. For those works, the libraries either buy several copies of the entire book, or, in about 10 cases each semester, are not able to keep the material on reserve, added Lanham.

Though the process is costly and time consuming. Lanham said, "that's the purpose of the research libraries."

Lamont normally carries one copy of a reading for every 10 students in a course up to a limit of 10.

Yesterday's memo was the latest in a variety of strateeies. Harvard has used to publicize the guidelines among the Faculty.

Lanham said the libraries had advertised in The Crimson and the Gazette this semester to alert professors to the requirements, and libraries stamp warnings on reprinted material telling students not to recopy it. Often, visiting of new professors are unaware of the early timetables the libraries follow, be said, adding, "This is just an issue than needs repetition.

Despite the heavy publicity surrounding the first copyright law suit two years ago, Harvard has not been the rarest of any similar legal actions. Undertaking the publicity efforts.