Primary Sources is an achievement obtainable in Act III. It involves the collection of People Lore items.
You can find which Journals you have by looking at your Achievements in game, under Campaign > Act III and scroll down to 'Primary Sources' and expand that menu.
Contents
Entries
Bloodstained Letter
Location: The Keep Depths Level 1
Quest: while doing "The Breached Keep"
"My dearest Jonathan, I hope this finds you well and that life at Bastion´s Keep is not too difficult. Arthur is growing up to be just like his father. I´m happy to hear you´ll be back in time for his birthday, and I´ll be praying every night for your safe return. - Brielle"
Ghom's Log
Location: The Larder top right corner there's a corpse with the log on it
Quest: The Breached Keep
"Unknown Text"
Journal of Hansan Haile, Captain
Location: Bastion's Keep Stronghold This book is by the feet of the vendor Vidar the Collector in a keepsake box
Quest: Any Quest
"Unknown Text"
Leah's Journal, Part 13
Location: Unknown
Quest: Unknown
"Unknown Text"
Leah's Journal, Part 14
Location: The Armory Inside Bastion's Hold, south of Leah and Adria. Her journal is on her desk in another room
Quest: Turning the Tide
"Unknown Text"
Leah's Journal, Part 15
Location: The Armory Inside Bastion's Hold, south of Leah and Adria. Her journal is on her desk in another room
Quest: The Breached Keep Part where you have to find the Bastion's Keep Larder
"Unknown Text"
Leah's Journal, Part 16
Location: The Armory Inside Bastion's Hold, south of Leah and Adria. Her journal is on her desk in another room
Quest: Machines of War
"Unknown Text"
Morgan's Jourrnal, part 1
Location: Skycrown Battlements On Morgan's satchel just north of the entrance
Quest: The Siege of Bastion's Keep
"Unknown Text"
Morgan's Jourrnal, part 2
Location: Stonefort In the middle-ish of the map, before the first catapault
Quest: Turning the Tide
"Unknown Text"
Morgan's Jourrnal, part 3
Location: The Keep Depths Level 1
Quest: while doing The Breached Keep
Looted of a guards body close to the door