Ключевые слова: academic, background, book, books, bookshelf, bookstore, collection, concept, cover, design, dictionary, document, education, element, encyclopedia, flat, graphic, icon, illustration, information, isolated, knowledge, learn, learning, library, literary, literature, many, object, old, page, read, reading, row, school, science, search, set, shelf, stack, study, studying, symbol, technology, text, textbook, university, vector, web, wisdom,