1. On distinct unit fractions whose sum equals 1;Burshtein;Discrete Math.,1973
2. N. Burshtein, All the solutions of the equation ∑i=1111xi=1 in distinct integers of the form xi∈3α5β7γ, Discrete Math., in press
3. Unsolved Problems in Number Theory;Guy,1981
4. Sur les décompositions de nombres rationnels en fractions primaires;Sierpiński;Mathesis,1956
5. C. Rivera, J. Ayala, The prime puzzles & problems connection, http://www.primepuzzles.net/