The author of this book is the Levenhstein Distance algorithm, the subject is the eucalyptus tree in "Fama y eucalipto", an excerpt from Historias de Cronopios y de Famas by Julio Cortázar, published in 1962 by Editorial Minotauro. Levenshtein distance, edit distance or word distance is an algorithm that operates in spell checkers. It is the minimum number of operations required to transform one word into another. An operation can be an insertion, deletion or substitution of a character. The algorithm was an invention of Russian scientist Vladimir Levenshtein in 1965.