PATENTS

张晓泉，曲丽, 2021, 支付信息费用的方法和系统，国家知识产权局专利号：****11070544.X。

Zhang, X. and Mo, G., 2015, Method and System for Using a Point System to Deliver Advertisement Emails and to Stop Spam, United States Patents and Trademarks Office, Number: 10/707,694.