| RefNo | Title | Date |
| RR/19/100 | Referee's report [page one] by Alfred Harker, on a paper 'The synthesis of a silicalcyanide and of a felspar' by James Emerson Reynolds | 30 October 1912 |
| RR/22/83 | Referee's report by Alfred Harker, on a paper 'The reduction of metallic oxides with hydrogen at high pressures' by Edgar Newbery and John Norman Pring | November 1915 |
| RR/22/90 | Referee's report by Alfred Harker, on a paper 'On the cause of movement and contortion in the Earth's crust' by Clement Reid | June 1915 |
| NLB/37/180 | Copy letter from Robert William Frederick Harrison to Dr A [Arthur] Smith Woodward FRS | 7 February 1908 |
| NLB/46/635 | Copy letter from Henry George Lyons, to Dr Charles William Andrews, Alfred Harker, Dr George Jennings Hinde, Clement Reid, Professor Albert Charles Seward, Professor William Whitehead Watts, Captain Thomas Henry Tizard, Professor John Walter Gregory | 7 October 1912 |
| NLB/47/617 | Copy letter from Robert William Frederick Harrison to Alfred Harker FRS | 4 March 1913 |
| NLB/47/629 | Copy letter from Robert William Frederick Harrison to Alfred Harker FRS | 6 March 1913 |
| NLB/51/4 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society to Alfred Harker, FRS | 18 November 1914 |
| RR/17/280 | Referee's report by Alfred Harker, on a paper 'Photographical notes on the products of the eruptions of May 1902 at the Soufriere in St Vincent' by John Smith Flett | 3 February 1908 |
| RR/22/27 | Referee's report by Alfred Harker, on a paper 'On the specific heat of steam at atmospheric pressure between 104°C and 115°C' by J H Brinkworth and Hugh Longbourne Callendar | May 1915 |
| RR/29/30 | Referee's report by Alfred Harker, on a paper 'The reduction of methylene blue by iron compounds' by Edward James Morgan and Juda Hirsch Quastel | April 1923 |
| RR/40/50 | Referee's report by Alfred Harker, on a paper 'Ball-and-socket jointing in basalt prisms' by F W Preston | 21 November 1929 |
| RR/19/101 | Referee's report [page two] by Alfred Harker, on a paper 'The synthesis of a silicalcyanide and of a felspar' by James Emerson Reynolds | 30 October 1912 |
| NLB/65/534 | Copy letter from William Bate Hardy, Secretary of the Royal Society; to Sir Aubrey Strahan, FRS | 14 November 1923 |
| EC/1902/08 | Harker, Alfred: certificate of election to the Royal Society | |
| NLB/54/532 | Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to Professor [Hugh Longbourne] Callendar, Chairman of the Physics and Chemistry Committee and FRS | 11 June 1917 |
| RR/64/25 | Referee's report by Alfred Harker, on a paper 'The geological history of the Lake Rudolf Basin, Kenya colony' by Vivian Ernest Fuchs | 28 November 1937 |
| RR/64/115 | Referee's report by Alfred Harker, on a paper 'The Royal Society expedition to Montserrat, B. W. I. - The volcanic history and petrology of Montserrat, with observation on Mt Pelé, in Martinique' by A G MacGregor | 6 October 1937 |