Following this guide + data from this page
File: /etc/nginx/global/referer-spam.conf
##
# Referrer exclusions
##
if ($http_referer ~ "(buttons-for-website\.com|darodar\.com|econom\.co|ilovevitaly\.co|kambasoft\.com|lumb\.co|7makemoneyonline\.com|ranksonic\.info|savetubevideo\.info|see-your-website-here\.com|semalt\.com|priceg\.com|srecorder\.com|descargar-musica-gratis\.net|54\.186\.60\.77|lomb\.co)") {
set $prohibited "1";