Formal:
* "Dr. Smith and Dr. Jones conducted the surgery together."
* "The patient was seen by both Dr. Lee and Dr. Garcia."
Informal:
* "Dr. Brown and Dr. Williams are partners in the practice."
* "My friend, Dr. Patel, and his colleague, Dr. Rodriguez, are doing great work."
Using titles only:
* "The doctors, both highly experienced in their field, collaborated on the research."
* "The surgeons, working together, performed a complex procedure."
Adding a descriptive phrase:
* "Dr. Thompson, a cardiologist, and Dr. Davis, a neurologist, were both consulted on the case."
* "The two pediatricians, Dr. Miller and Dr. Chen, examined the child."
Remember to choose the style that best suits your writing and the formality of the situation.