Add captcha to website

recaptcha mod_rewrite mod_rewrite captcha https://manuelbaumann.com/2012/04/captcha-protect-your-website-using-apaches-mod_rewrite-to-expel-google-facebook-and-co/

Apache2-reCaptcha-0.3 Apache2::reCaptcha

http://search.cpan.org/~analog/Apache2-reCaptcha-0.3/lib/Apache2/reCaptcha.pm

mod_captcha

https://sourceforge.net/projects/mod-captcha/

others

perimeterx https://github.com/PerimeterX/mod_perimeterx#installation

perimeterx Apache2-reCaptcha-0.3