Gauss's Lemma


 * Gauss's Lemma (Number Theory): relating the number of least positive residues of a prime to its Legendre symbol;
 * Gauss's Lemma (Polynomial Theory)
 * Gauss's Lemma on Primitive Polynomials: the product of two primitive polynomials is primitive.
 * Gauss's Lemma on Irreducible Polynomials: concerning the reducibility of polynomials
 * Gauss's Lemma on Unique Factorization Domains