sodium 4-hydroxynaphthalenesulphonate, 4-hydroxy-1-naphthalenesulfonic acid sodium, SODIUM 1-NAPHTHOL-4-SULFONATE, NEVILE-WINTER'S ACID SODIUM SALT, NEVILLE-WINTHER ACID SODIUM SALT, SODIUM 4-HYDROXY-1-NAPHTHALENESULFONATE, A-NAPHTHOSULFONIC ACID SODIUM SALT, 4-hydroxy-naphthalene-1-sulfonic acid sodium salt, NW ACID, 4-hydroxy-1-naphthalenesulfonic acid sodium salt, sodium 4-hydroxynaphthalene-1-sulfonate, SODIUM NAPHTHOL SULFONATE, 1-HYDROXY-4-SULFONAPHTHALENE SODIUM SALT, NEVILLE WINTHER ACID