Here are our modern sources:
Picts: History and Heritage (documentary)
Picts: Symbols and Signs (documentary)
Bridei Mac Bili: King of the Picts (documentary)
Konstam, Angus. Strongholds of the Picts: The Fortifications of Dark Age Scotland. Osprey Press, February 20, 2013.
Forster, Sally M. Picts, Gaels and Scots: Early Historic Scotland. Birlinn Press, November 1, 2014.
Pictish Nation: The Pictish Kings
Scotland: Rome’s Final Frontier: 2012 documentary by Dr. Fraser Hunter
“The Problem of the Picts.” Current Archaeology, June 4, 2020
Strauss, Mark. “Want to Build a Strong Fortress? Set it On Fire.” National Geographic, March 3, 2016.
Orkneyjar. “The Picts: The Enigma of the Symbol Stones.”
Fox, Alex. “Ancient Hillfort May Be Largest Known Pictish Settlement in Scotland.” Smithsonian Magazine, May 18, 2020
Johnson, Ian. “The Truth About the Picts.” The Independent, October 23, 2011
Kathryn M. Hudson & Wayne E. Harbert. “Pictish Ogam Stones as Representations of Cross-cultural Dialogue.”
Ross, Shan. “One in Ten Scots Men Descended from Picts.” The Scotsman, March 25, 2013.
Lore O’Brien: Celtic Woad: An Authentic Resource?
And some ancient sources:
Gildas’ On the Ruin of Britain (J.A. Giles translation)
Cassius Dio’s Roman History (Earnest Cary translation)
Bede’s Ecclesiastical History of England (Dr. Giles translation)
Rex Pictorum: History of the Kings of the Picts.
Medieval Sourcebook: Cain Adamnain: An Old-Irish Treatise on the Law of Adamnan. (Kuno Meyer translation)
Medieval Sourcebook: Adamnan: Life of St. Columba.
Chronicle of the Kings of Alba (A.O.Anderson translation)
Ammianus Marcellinus: Roman Antiquities (J.C. Rolfe translation)