20992 Herbert Bilharz: Primdivisoren mit vorgegebener Primitivwurzel.
Math. Annalen 114 (1937), 476-492.

20988 Michael Drmota: Merkwürdige Dezimalzahlen. Internet ca. 1998, 22p.

Dorian Goldfeld (Morris?): Artin's conjecture on the average.
Mathematika 15 (1968), 223-226.

Rajiv Gupta/M. Ram Murty: A remark on Artin's conjecture.                   
Inventiones Math. 78 (1984), 127-130.

D. Heath-Brown: Artin's conjecture for primtive roots.
Quarterly J. Math. Oxford 37 (1986), 27-38.

20991 Christopher Hooley: On Artin's conjecture.
J. Reine Angew. Math. 225 (1967), 209-220.

Derrick Lehmer/Emma Lehmer: Heuristics Anyone?
In Studies in Mathematical Analysis and related topics, pp. 202-210, Stanford                 
University Press, 1962.

20995 Shuguang Li/Carl Pomerance: Primitive roots - a survey. Internet 2002, 13p.

20993 Keith Matthews: A generalization of Artin's conjecture for
primitive roots. Acta Arithm. 29 (1976), 113-130.

24882 Pieter Moree: Artin's primitive root conjecture - a survey.
Integers 12A (2012), 100p.

5130 M. Ram Murty: Artin's conjecture for primitive roots.
Math. Intell. 10/4 (1988), 59-67.

20989 Francesco Pappalardi: On Artin's conjecture for primitive roots.
Ph.D. thesis McGill Univ. 1993, 109p.

20990 Francesco Pappalardi: On simultaneous primitive roots. Internet 2006, 7p.

20999 A. Paszkiewicz: A new prime p for which the least primitive root
mod p and the least primitive root mod p^2 are not equal.
Math. Comp. 78/266 (2009), 1193-1195.
The new prime is 6692367337.