Paul Rolland's "Materials and Motion Techniques for Individual or Class Instruction" Margaret Rowell: Co-Author, cello bookEdward Krolick: Co-Author, bass bookThese are out of print, unfortunately. Look for them in a library near you!
I used this book when I first started teaching. The techniques included are excellent. I left my copies in the DePauw University Library thinking I could get more copes later. But, alas, I couldn't.