- FondsLarmor - Papers of Sir Joseph Larmor
- SeriesLetters - Letters to and from Larmor
- SubseriesTo Larmor - Letters to Larmor
- FileHeitland (Misc) - Letters from William Emerton Heitland. One letter by JL in reply.
- ItemHE3/3 - Autograph letter, signed, from St John's College
- ItemHE3/4 - Autograph letter, signed, from St John's College. Attached is JL's reply.
- ItemHE3/5 - Autograph letter, signed, from Cambridge
- ItemHE3/6 - Autograph letter, signed, from Cambridge
- ItemHE3/7 - Autograph letter, signed, from Cambridge
- ItemHE3/8 - Autograph letter, signed, from St John's College