Isomotifs de dimension inferieure ou ´ ` au n

Once having recollected some of V. Voevodsky's results as found in (Voe00), we prove the equivalence of categories, announced in loc. cit. § 3.4 (p. 218), between the derived category of 1-isomotives of P. Deligne on a perfect field and the triangulated category of geometric effective motives of dimension less than or equal to 1.