Sometimes the article is not used where we naturally expect to find it in accordance with the rules. No change of meaning is observed in these cases.

The article is often omitted in newspaper headings, telegrams, in stage directions.

Gas Blast Kills Woman. (Daily Worker)

Girl Gymnast Keeps Title. (Moscow News)

The article is often omitted with homogeneous members closely connected with each other and joined by the conjunction and. In most cases, they go in pairs.

The breakfast was taken away, and that meal over, it was the general custom of uncle and niece to separate. (Ch. Bronte)