在全国统一的标准书次号尚未确立之前,由于种次号具有简单、方便、不重号和号码短等优点,目前有80呖以上的各类图书馆采用种次号作为书次号。采用种次号一般要使用种次号记录卡(也叫种次号顺序卡),因为它比代号卡更为方便。现在使用的种次号记录卡是在种次号码右边的空格内打“√” Before the unified national standard number has been established, due to the advantages of simple number, convenience, non-heavy number and short number, there are currently more than 80 types of libraries adopting the unique number as the book number. The use of kind numbers generally use the kind of number card (also called sort order card), because it is more convenient than the code card. Now use the kind of number card is in the number of spaces to the right of playing a “√”