Allan Kass

Title: Obstetrical Nurse
Author: Jane Converse
Publisher: Signet
Published: June 1972, ©1972
Illustrator: Allan Kass

His signature is in the lower left-hand corner.

"I love you, Lon. I'm never going to stop loving you!" Nurse Marguerite Lowell longed to say it to Dr. Lon Webster. Longed to kindle a response in his heart. Working so closely with him, Marguerite found her attraction to the handsome young doctor growing stronger each day. And more hopeless, for Lon made no secret of his infatuation with the hospital's provocative blond receptionist. When Dr. Warren Leash, Chief of Obstetrics, proposed, Marguerite felt caught in an emotional trap. Warran was a man she deeply admired—but could she love him? Should she fight for the man she wanted—or settle for a sensible marriage? The turmoil in her heart grew, until a fateful event brought Marguerite within reach of the love she had always dreamed of ...

Allan Kass

Title: Penthouse Nurse
Author: Jane Converse
Publisher: Signet
Published: April 1974, ©1974
Illustrator: Allan Kass

This is credited by the blog Allan Kass, Illustrator of Book Covers.

Actually, it was a dream assignment—private duty nurse to wealthy Jim Orr in his lavish penthouse. But to Carrie Linden it meant only a chance to work with Ken Delaney, Jim's doctor—a chance to be near the man she secretly loved. Perhaps then their friendship might grow into something more. But Ken treated her as just an old friend and a capable, dedicated nurse. But Dr. Michael Carlisle saw her differently, and Carrie, feeling so lonely, found herself accepting his persistent attentions. Soon she became more and more drawn to the suave and handsome doctor, yet the image of Ken still haunted her daydreams. Was she a romantic fool to think that Ken would ever care for her? Or should she erase him from her life—and her heart...?

Lou Marchetti

Title: Crystal Manning, Maternity Nurse
Author: Nan Lowry
Publisher: Paperback Library
Published: July 1964, ©1964
Illustrator: Lou Marchetti

This is not credited, but is very much in his style.

As the young head nurse of a busy maternity ward, Crystal Manning often went beyond the call of duty to bring compassion to her patients. Then one of her kind gestures backfired. She was accused of kidnaping a new-born baby. Nurse Manning  needed all the help she could get at this crucial time, particularly from the two men who loved her: Lloyd Norris, a successful attorney; and Mike Dorand, the friendly young doctor with whom she worked. As a nurse, she knew that she would have to clear her name or neither man would want her for his wife. 

Uldis Klavins

Title: Disaster Area Nurse
Author: Arlene Hale
Publisher: Ace
Published: ©1965
Illustrator: Uldis Klavins
Review available

The artist is credited at an auction house web site where the original artwork was sold. 

The thunder roared and crashed about them—but Nurse Lynn Lawrence felt that the wildness of the storm was rivaled by the frantic racing of her own thoughts. She cast a glance at her fiancé, Greg Avery. Beside him, huddled helplessly, was the pretty Dawn Evans. There was no doubt that Greg was paying a great deal of attention to comforting Dawn—too much, Lynn thought. But there was another in the group of flood-marooned strangers. He was handsome, and smiled at Lynn in a way that sent the heart fluttering. Surely things would right themselves once they got back to civilization. But in a disaster like this, a short time could lead to a broken-hearted eternity.

Victor Kalin

Title: Jane Arden Staff Nurse
Author: Kathleen Harris
Published: ©1957
Publisher: Popular Giant G-497
Illustrator: Victor Kalin

His signature in in the lower left-hand corner.

As staff nurse in a fast-paced university hospital, Jane Arden was sure her new job would leave her no time for men. She was also sure she’ never forget the man she’d loved all her life, and had lost in a tragic plane accident. But then she learned that time has a way of healing all wounds … and a new love a way of replacing the old.

Forté

Title: Jane Arden Head Nurse
Author: Kathleen Harris
Publisher: Popular Library #G561
Published: Nov 1961, (c)1959
Illustrator: Forté

His signature is in the middle left-hand side.

When Jane Arden took over as Head Nurse at the Friedmont Hospital, she knew that the job had many pitfalls. But it was an exciting challenge in a field she loved. Then she met Jeff Wallace, the young, outspoken Chairman of a strife-torn Hospital Board. Jane needed his support and his friendship. She saw him more and more. At first when people started to talk she didn't care. But she had enemies who wanted to get rid of her any way they could. Suddenly Jane realized that her whole career was threatened--as well as her growing love for Jeff. Was it already too late?

Jack Harman

Title: Nurse Templar
Author: Anne Weale
Publisher: Harlequin #578
Published: Dec 1966, (c)1960
Illustrator: Jack Harman

His signature is in the lower left-hand corner.

The bustling atmosphere of a brand-new, modern residential community is the background of this charming story of a young midwife, the pleasant doctor who loved her, and the not-so-pleasant but oh! so attractive man who did not. Linden knew she was being foolish to think of Randal Craig. he was too wealthy, his family too exclusive, for her. She must put him firmly out of her mind ... but that was easier said than done.