Vaughan, R. C.; Wooley, T. D. (1994), “Further improvements in Waring's problem. II. Sixth powers”, Duke Mathematical Journal76 (3): 683–710, doi:10.1215/S0012-7094-94-07626-6, MR1309326
Brudno, Simcha (1976), “Triples of sixth powers with equal sums”, Mathematics of Computation30 (135): 646–648, doi:10.2307/2005335, MR0406923
Bremner, Andrew; Guy, Richard K. (1988), “Unsolved Problems: A Dozen Difficult Diophantine Dilemmas”, American Mathematical Monthly95 (1): 31–36, doi:10.2307/2323442, MR1541235
Vaughan, R. C.; Wooley, T. D. (1994), “Further improvements in Waring's problem. II. Sixth powers”, Duke Mathematical Journal76 (3): 683–710, doi:10.1215/S0012-7094-94-07626-6, MR1309326
Brudno, Simcha (1976), “Triples of sixth powers with equal sums”, Mathematics of Computation30 (135): 646–648, doi:10.2307/2005335, MR0406923
Bremner, Andrew; Guy, Richard K. (1988), “Unsolved Problems: A Dozen Difficult Diophantine Dilemmas”, American Mathematical Monthly95 (1): 31–36, doi:10.2307/2323442, MR1541235