There are 4 unique codex entries in the Persons of Note section on Rishi. 2 are accessible to all players regardless of class or faction and 2 are class specific.
Arankau is obtained from speaking with Arankau during "The Revanites Revealed" mission.
Codex type: Persons of Note | Faction: Both | Class: All
Associated Achievement: None
Commodore Margok is obtained from killing Commodore Margok during "Heart of the Aggressor" mission.
Codex type: Persons of Note | Faction: Both | Class: All
Associated Achievement: None
Master Kutri O'a is obtained from speaking with Master O'a during "Barsen'thor's Legacy" mission.
Codex type: Persons of Note | Faction: Republic | Class: Jedi Consular
Associated Achievement: None
Thera Markon is obtained from speaking with Thera Markon during "The Ones Left Behind" mission.
Codex type: Persons of Note | Faction: Imperial | Class: Bounty Hunter
Associated Achievement: None