EducationBusiness
EducationBusiness(McGrawHill+PearsonEducation+…) VS Open Source Textbooks: APEX Calculus + OpenIntro Statistics
教育商业： 商业教科书服务商： Pearson Education, McGrawHill, … 开源英文原版教科书： leanpub.com: OpenIntro.org: Statistics APEX: Calculus ......