Resources on Primacy and the Filioque

This post is for the assistance of those seeking more information on the subjects of:

• Primacy in the Universal Church
• The non-Orthodox addition of Creedal article "filioque" ("and the Son") within the statement proclaiming the procession of the Holy Spirit  
  

Position of the Moscow Patriarchate on the Problem of Primacy in the Universal Church
https://mospat.ru/en/2013/12/26/news96344/

"Filioque" on Orthodoxwiki
http://orthodoxwiki.org/Filioque