To maneuver at the slowest airspeed at which the airplane is capable of maintaining controlled flight without indications of a stall—usually 3 to 5 knots above stalling speed.
AC 61-67C Chapter 2. Flight Training: Stalls
AFH Ch-04 (03) Slow Flight
Cessna SOPM 2-30 Maneuvering During Slow Flight
Private Pilot ACS Page 40 Task A. Maneuvering During Slow Flight