图论，研究拓扑学，工程设计等的国外经典教程，英文原版，非常清晰，非扫描图片-Graph theory, topology studies, engineering design tutorials foreign classics, English original, very clear, non-scan images

图片处理的好例子，学习图像处理的经典图片呵呵！-A good example of image processing, and image processing to learn classic picture Oh!