diff --git a/docs/case/case1.md b/docs/case/case1.md
index 495f2c6cc2..e0331809b3 100644
--- a/docs/case/case1.md
+++ b/docs/case/case1.md
@@ -338,7 +338,7 @@ GOOS=darwin GOARCH=amd64 go build -o goecs_darwin
 
 ## 致谢
 
-感谢 [he.net](https://he.net) [bgp.tools](https://bgp.tools) [ipinfo.io](https://ipinfo.io) [ip.sb](https://ip.sb) [cheervision.co](https://cheervision.co) [scamalytics.com](https://scamalytics.com) [abuseipdb.com](https://www.abuseipdb.com/) [virustotal.com](https://www.virustotal.com/) [ip2location.com](ip2location.com/) [ip-api.com](https://ip-api.com) [ipregistry.co](https://ipregistry.co/) [ipdata.co](https://ipdata.co/) [ipgeolocation.io](https://ipgeolocation.io) [ipwhois.io](https://ipwhois.io) [ipapi.com](https://ipapi.com/) [ipapi.is](https://ipapi.is/) [ipqualityscore.com](https://www.ipqualityscore.com/) [bigdatacloud.com](https://www.bigdatacloud.com/) 等网站提供的API进行检测，感谢互联网各网站提供的查询资源
+感谢 [he.net](https://he.net) [bgp.tools](https://bgp.tools) [ipinfo.io](https://ipinfo.io) [ip.sb](https://ip.sb) [cheervision.co](https://cheervision.co) [scamalytics.com](https://scamalytics.com) [abuseipdb.com](https://www.abuseipdb.com/) [virustotal.com](https://www.virustotal.com/) [ip2location.com](https://ip2location.com/) [ip-api.com](https://ip-api.com) [ipregistry.co](https://ipregistry.co/) [ipdata.co](https://ipdata.co/) [ipgeolocation.io](https://ipgeolocation.io) [ipwhois.io](https://ipwhois.io) [ipapi.com](https://ipapi.com/) [ipapi.is](https://ipapi.is/) [ipqualityscore.com](https://www.ipqualityscore.com/) [bigdatacloud.com](https://www.bigdatacloud.com/) 等网站提供的API进行检测，感谢互联网各网站提供的查询资源
 
 感谢