Fotografie: Ivor Grattan-Guinness 1989, in: Joseph W. Dauben/ Niccolò Guicciardini/ Albert Lewis/ Karn Hunger Parshall/ Adrian C. Rice, cIvor Grattan-Guinness (June 23, 19413December 12, 1914)d, Historia Mathematica 42 (2015)
V. Peckhaus, Fotografie: Ivor Grattan-Guinness 1989, in: Joseph W. Dauben/ Niccolò Guicciardini/ Albert Lewis/ Karn Hunger Parshall/ Adrian C. Rice, “Ivor Grattan-Guinness (June 23, 1941–December 12, 1914)”, Historia Mathematica 42 (2015), 2015.