C.I. Pigment Red 52, calcium salt (1:1); 2-Naphthalenecarboxylic acid, 4-(2-(4-chloro-5-methyl-2-sulfophenyl)diazenyl)-3-hydroxy-, calcium salt (1:1); calcium (4E)-4-[(4-chloro-5-methyl-2-sulfonatophenyl)hydrazono]-3-oxo-3,4-dihydronaphthalene-2-carboxylate