Ross, P.M. (1975). "On Chen's theorem that each large even number has the form (p1+p2) or (p1+p2p3)". J. London Math. Soc. (2)10,4: 500–506. doi:10.1112/jlms/s2-10.4.500
Y.C. Cai: Chen’s Theorem with Small Primes. In: Acta Mathematica Sinica. 2000, Band 18, Seiten 597–604 (doi:10.1007/s101140200168).
