A crown of sonnets or sonnet corona is a sequence of sonnets, usually addressed to one person, and/or concerned with a single theme. Each of the sonnets explores one aspect of the theme, and is linked to the preceding and succeeding sonnets by repeating the final line of the preceding sonnet as its first line. The first line of the first sonnet is repeated as the final line of the final sonnet, thereby bringing the sequence to a close. Heroic crown An advanced form of crown of sonnets is also called a sonnet redoublé or heroic crown, comprising fifteen sonnets, in which the sonnets are linked as described above, but the final binding sonnet is made up of all the first or the last lines of the preceding fourteen, in order. The fifteenth sonnet is called the Mastersonnet. This form was invented by the Siena Academy, which was formed in 1460, but there are no existing crowns of sonnets written by them. The form was first described by Giovanni Mario Crescimbeni in his work L'Istoria della volgar poesia (History of Vernacular Poetry), published in Venice, 1731 and later by P.G. Bisso in his Introduzione alla volgar poesia (Introduction to Vernacular Poetry), published in Venice, 1794. A variation on the form is sometimes used in which the binding sonnet is the first sonnet, and subsequent sonnets end with a line taken from it in order. The oldest complete crown which survived time was published in 1748. It was written by a group of 14 poets to celebrate the birth of the ideal woman: Corona di rime per festeggiare il natalizio giorno di fille. John Donne wrote La corona, a set of 7 sonnets which are linked together. Because there are only 7 of them and because there's no Mastersonnet, La corona is not a full heroic crown. Probably the first full crown of sonnets in English is Lady Mary Wroth's A Crown of Sonnets Dedicated to Love which is from circa 1620. The children's book A Wreath for Emmett Till by Marilyn Nelson also follows the form of a heroic crown of sonnets. Another well-known and frequent author of contemporary crowns of sonnets is Marilyn Hacker. "Intertidal", a collaborative crown of sonnets by contemporary poets Judith Barrington, Annie Finch, Julie Kane, Julia Lisella, D'Arcy Randall, Kathrine Varnes, and Lesley Wheeler, was organized through discussion on the Wom-Po listserv and published in