30 Progressive Exercises for Beginning String Orchestra. EXERCISES ONLY. Teacher’s book and parts. for Violin,Viola,Cello,Double Bass,String Orchestra written by Laura C. Quijada Ortíz. The format of this sheet music is Score,Set of Parts and it’s published by Laura Quijada. 30 Progressive Exercises for Beginning String Orchestra. EXERCISES ONLY. Teacher’s book and parts. is part of the following sheet music categories: Method,Etudes and Exercises,Classroom.