I only know that foreign language bookstores in Shanghai sell them.

A. Shanghai Foreign Language Bookstore Guidu Store -(02 1)62485245 Shanghai International Guidu Hotel Office Building, No.228 Huashan Road

B. Foreign Language Bookstore (Fuzhou Road No.2 Branch) -(02 1)63223200 No.446 Fuzhou Road, Huangpu District (near Fujian Middle Road)

C Shendong Foreign Language Bookstore (Quanguo Road Branch) -(02 1)55057938 No.31KLOC-0/Quanguo Road, Yangpu District

D.No. Jiangchang Road 1406, Storage and Transportation Department of Shanghai Foreign Language Bookstore, Shanghai Foreign Language Book Company

E foreign language bookstore (new railway station store) -(02 1)63 174944 No.258 moling road, Zhabei district (near the south square of the railway station)

F. Next to Times Square, Nanquan Road, Pudong New Area (opposite to Pudong Branch of Shanghai Foreign Languages Bookstore)

Label: Yaohan