There's a whole niche of books in Spanish that are designed as presents for family members and loved ones. Filled with sweet messages or quotations of famous authors, these books function as extended Hallmark cards, and, like cards, they help people communicate feelings they might otherwise have trouble expressing. Some of the most noteworthy books in this genre are published by the Argentine house of Vergara & Riba Editoras. These three books all contain charming, full-color illustrations and original text. The first, designed as a gift for a child from his or her parents, offers young ones bits of advice, such as ""when one door closes, look around: another one opens."" The second is a paean to motherly love, and the last voices a grandmother's affection for her grandchild. Though not terribly sophisticated, these books are produced with an eye to quality and, if properly displayed for impulse purchases, they should do well in large bookstores. Marcela Valdes, ""Cr ticas""