http://wenku.baidu.com/view/4cc4ccbec77da26925c5b000.html
http://stackoverflow.com/questions/5789426/system-collections-queuet-threads-locking-and-synchronization
http://blog.csdn.net/ZOU_SEAFARER/article/details/4220283
原文:http://www.cnblogs.com/pengzhen/p/3579437.html