Here is a class focusing on the Rectus Abdominis, Internal and External Obliques and Transverse Abdominis. 

The amazing abdominals have a number of roles. They are arranged in layers around the torso along the front and sides and function to support the spine and the organs. 

The main function of the abdominal muscles is to stabilise the ribs and pelvis against the force of gravity. 

You will need a yoga brick for this class. Have fun :)