Roy Lichtenstein, 73, the prolific, ironic and highly cerebral pioneer of the pop art movement best known for the stylized comic book-like images that made him one of the most celebrated artists of the day, died of pneumonia Sept. 29 at New York University Medical Center in New York.

A classically trained painter and former adherent to the abstract expressionist school that dominated American art in the post-World War II era, Mr. Lichtenstein established his reputation in 1961 with a picture called "Look, Mickey, I've Caught a Big One." It showed Mickey Mouse and Donald Duck sitting next to a fishing hole.

Over the years, his subjects included bubble gum wrappers, a golf ball, a poster for Kitty Litter, Chinese landscapes, ancient temples and interpretations of some of the most famous works of modern art, such as "The Scream" by Edvard Munch. His signatures included the oversize benday dots used by photoengravers and captions that said "Pop!" "Wow!" and "Bam!" He frequently worked on a large scale.

"Drowning Girl," which he produced in 1963, included a caption that said, "I don't care! I'd rather sink -- than call Brad for help!" A work on war had a balloon that said, "I pressed the fire control . . . and ahead of me rockets blazed into the sky."

Mr. Lichtenstein's purpose was to provide a counterpoint to the seriousness of the art establishment. Although he received a mixed reaction from critics -- a writer in the New York Times declared in 1963 that he was "one of the worst artists in America" -- he was instantly popular with collectors. Later critics said his work evoked the playfulness of the Dadaists in the early years of this century. His pictures and sculptures were widely praised for their wit, intelligence and good humor.

Mr. Lichtenstein was best known, perhaps, for his prints. He achieved the benday dot effect by painting through screens. He sometimes used toothbrushes and sponges. His pictures were large and bold, with bright colors and sharply delineated lines.

In time, Mr. Lichtenstein's work was added to the permanent collections of major museums around the world, and his prints were the subject of major shows at the National Gallery of Art and other leading museums. In the early 1990s, one of his cartoon pieces brought a price of $6 million from a Japanese collector.

Mr. Lichtenstein told art critic John Gruen that when he first realized what he was doing, "it offended my own sense of taste. This was, without question, contrary to everything one had been taught about matters of style and substance, and so forth."

Nonetheless, he said, he found he could not produce artworks any other way.

"I didn't think anyone would be interested in them -- and I really didn't care," he said. "That part wasn't important. What was important was that I was doing them."

In a review of a major retrospective of Mr. Lichtenstein's work at the Guggenheim Museum in New York in 1993, Time magazine art critic Robert Hughes described the artist as "the great academician of the pop movement." He added, however, that "after a while, it isn't very interesting to be shown that just about anything can be turned into a Lichtenstein, congealed in his cryogenic style."

Mr. Lichtenstein was born in New York on Oct. 27, 1923. After high school, he studied at the Art Students League. He graduated from Ohio State University, where he majored in art. He later received a master's degree in art from Ohio State. During World War II, he served in the Army.

In the 1950s, he had several teaching appointments, and in 1960, he joined the faculty of Douglass College at Rutgers University. Colleagues there included artists Claes Oldenburg, Allan Kaprow and Robert Watts.

An interest in Americana led Mr. Lichtenstein to do a number of pictures of cowboys and Indians in modern art styles.

Mr. Lichtenstein had residences and studios in New York City and Southampton on Long Island.

His marriage to Isabel Wilson ended in divorce. He later married Dorothy Herzka.

Survivors include two sons from his first marriage.

Leo Castelli, whose SoHo gallery had represented Mr. Lichtenstein since 1961, offered this assessment upon the artist's death: "He had a very original mind. Not only were his images quite wonderful and unexpected, but {so was} the quality of his art. His contribution to art history is just enormous." ASA JAMES BROWN Chiropractor

Asa James Brown, 80, a chiropractor who practiced in Arlington and Alexandria from 1951 to 1981 and was chairman of the board of the American Chiropractic Association, died Sept. 28 at the Potomac Center nursing facility in Arlington. He had lived in the Washington area off and on since 1939.

Dr. Brown was born in Charter Oak, Iowa. He was a graduate of Yankton College in South Dakota and Lincoln Chiropractic College in Indianapolis. He served in the Navy in Trinidad and Tobago during World War II.

Dr. Brown practiced elsewhere in Virginia before retiring in 1993.

He taught in the Sunday school of First Baptist Church in Alexandria.

His wife, Virginia Hansen Brown, died in 1985, and a son, James Brown, died in 1949.

Survivors include six children, Carole Pollara of Silver Spring, Diane Hancock and Peter Brown, both of Williamsburg, Douglas Brown and Jeffrey Brown, both of Alexandria, and Martin Brown of Fairfax; a brother, Roy C. Brown of Rockville; a sister, Merle Bryan of Forest Grove, Ore.; 14 grandchildren; and a great-granddaughter. BARRY SHERMAN Media Consultant

Barry Sherman, 78, who retired in the early 1990s as a self-employed media consultant, died Sept. 28 at George Washington University Hospital after stomach surgery. He lived in McLean.

Mr. Sherman was a native of Plymouth, Pa., and a graduate of Pennsylvania State University who also studied music at George Mason University. He served in Army during World War II.

Early in his career, he was a radio announcer in the New York area and in Richmond. He also managed radio stations in Knoxville, Atlanta and Scranton.

Before moving to the Washington area in 1980, Mr. Sherman was national director of marketing in New York for NBC and for classical music station WNCN.

He worked in the underwriting marketing offices of the Kennedy Center and National Public Radio before becoming a media consultant. He was a broker of radio stations and helped stations plan programming.

Mr. Sherman was a cantor at Adas Israel Congregation in Washington and at a Baltimore congregation, and he sang in the New Dominion Chorale and Adas Israel choir.

He had small roles in two television miniseries, one on George Washington and the other adapted from James A. Michener's "Space." Mr. Sherman was a member of the Screen Actors Guild, American Federation of Television and Radio Artists and the Broadcast Pioneers.

His marriage to Miriam Savage ended in divorce.

Survivors include his wife, Dr. Muriel Levin of McLean; two children from his first marriage, Deborah Leslie Sherman of East Northport, N.Y., and Jan Michael Sherman of Richmond, Calif.; a brother; two sisters; and two grandsons. JENNIE SUTHERLAND ASBILL Country Club Member

Jennie Sutherland Asbill, 97, a member of Columbia Country Club, died of a heart ailment Sept. 28 at her home in Chevy Chase. She had lived in the Washington area since 1934.

She was a native of Jacksonville, Fla., and a graduate of Goucher College.

Her husband, Mac Asbill Sr., and son, Mac Asbill Jr., died in 1992.

Survivors include four grandchildren and 12 great-grandchildren. ARDELLE IRVING HUMPHREY Secretary

Ardelle Irving Humphrey, 98, a Navy secretary who retired in 1959 after 41 years with the legal office of the Bureau of Yards and Docks, died of cardiac arrest Sept. 28 in the Wilson Health Care Center at Asbury Methodist Village in Gaithersburg.

She was born in Loudoun County and was a graduate of the Hume School there. She served in the Navy as a Yeomanette during World War I.

She was a volunteer at the Central Union Mission in Washington and a member of Mount Vernon Place United Methodist Church and Grace United Methodist Church in Gaithersburg. She was a charter member of the Women in Military Service for America.

She leaves no immediate survivors. WILLIAM JOSEPH LYNCH Air Force Chief Warrant Officer

William Joseph Lynch, 88, a retired Air Force chief warrant officer who later was a civilian personnel officer at Andrews Air Force Base, died Sept. 24 at the Veterans Hospital at Perry Point, Md., after a heart attack.

Mr. Lynch, a resident of Camp Springs, was born in New York. He began his military career in 1927 in a horse cavalry unit at Fort Myer, where he participated in the "Galloping Blacks" exhibition team. Later, he served in Panama and as a firearms instructor at the U.S. Military Academy at West Point. During World War II, he was host of a New York radio broadcast that featured interviews with celebrities in uniform.

After the war, he transferred to the Air Force, served in the Korean War and worked on educational programs in Florida.

In 1957, he retired from active duty and settled in the Washington area. For 14 years as a civilian, he directed personnel services for the Air Research and Development Command at Andrews Air Force Base.

He participated in the Home Rule Charter movement in Prince George's County and won several Citizen of the Year awards from the Camp Springs Citizens Association.

His first wife, Anna Mancuso Lynch, died in 1945. Survivors include his wife of 51 years, Virginia Mary Lynch of Camp Springs; their daughter, Mara Seaforest Charvonia of Warrenton; and a half brother. JOYCE L. STUBBS Telephone Clerk

Joyce L. Stubbs, 69, a retired telephone company clerk, died of congestive heart failure Sept. 20 at Shady Grove Adventist Hospital.

Mrs. Stubbs, who lived in Rockville, was born in Chicago.

She was a nurse's aide in Chicago, then a long-distance operator and clerk at Illinois Bell.

In 1972, she moved to the Washington area and worked for C&P Telephone Co. and Bell Atlantic before retiring in 1993.

Her avocations included knitting, crocheting and reading English history.

Her marriage to Charles Triner ended in divorce.

Survivors include her husband of 36 years, J. Earl Stubbs of Rockville; two children from her first marriage, Barbara DeSonia of Rockville and Michael Triner of Santa Barbara, Calif.; a half brother; three half sisters; and two granddaughters. Special correspondent Judd Tully, in New York, contributed to this report.