Peel the oranges and cut the inside into cubes. Grate the outer yellow rind of the lemons and peel them. Chop their insides finely.
Leave them for 1 night, and the next day, add the remaining sugar. Put the mixture to boil until the standard density for jams is reached, add the grated rind and stir regularly. Remove the foam from time to time during cooking.
Place the jam in dry and slightly warmed jars. Seal them well.