Information:  - Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, and the Mediterranean Sea to the south. To the east and southeast, Europe is generally considered as separated from Asia by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways of the Turkish Straits. Yet the non-oceanic borders of Europea concept dating back to classical antiquityare arbitrary. The primarily physiographic term "continent" as applied to Europe also incorporates cultural and political elements whose discontinuities are not always reflected by the continent's current overland boundaries.  - The formes fixes ( singular forme fixe , `` fixed form '' ) are the three fourteenth - and fifteenth - centuries French poetic forms : the ballade , rondeau and virelai . Each was also a musical form , generally a chanson , and all consisted of a complex pattern of repetition of verses and a refrain with musical content in two main sections . All three forms can be found in thirteenth - century sources but a fifteenth - century source gives Philippe de Vitry as their first composer while the first comprehensive repertory of these forms was written by Guillaume de Machaut . The formes fixes stopped being used in music around the end of the fifteenth century , although their influence continued ( in poetry they , especially the rondeau , continued to be used ) . Sometimes forms from other countries and periods are referred to as formes fixes . These include the Italian fourteenth century madrigal and later ballata and barzelletta , the German bar form , Spanish 13th century cantiga , and the later canción , and villancico .  - A chanson ("song", from Latin "cantio", gen. "cantionis") is in general any lyric-driven French song, usually polyphonic and secular. A singer specializing in chansons is known as a "chanteur" (male) or "chanteuse" (female); a collection of chansons, especially from the late Middle Ages and Renaissance, is also known as a chansonnier.  - Poetry (the term derives from a variant of the Greek term, "poiesis", "making") is a form of literature that uses aesthetic and rhythmic qualities of languagesuch as phonaesthetics, sound symbolism, and metreto evoke meanings in addition to, or in place of, the prosaic ostensible meaning.  - Latin (Latin: ) is a classical language belonging to the Italic branch of the Indo-European languages. The Latin alphabet is derived from the Etruscan and Greek alphabets.  - A refrain (from Vulgar Latin "refringere", "to repeat", and later from Old French "refraindre") is the line or lines that are repeated in music or in verse; the "chorus" of a song. Poetic fixed forms that feature refrains include the "villanelle", the "virelay", and the "sestina".  - The Late Middle Ages or Late Medieval Period was the period of European history generally comprising the 14th and 15th centuries (c. 13011500). The Late Middle Ages followed the High Middle Ages and preceded the onset of the early modern era (and, in much of Europe, the Renaissance).  - A sestina (Old Occitan: "cledisat" ; also known as "sestine", "sextine", "sextain") is a fixed verse form consisting of six stanzas of six lines each, normally followed by a three-line envoi. The words that end each line of the first stanza are used as line endings in each of the following stanzas, rotated in a set pattern.  - Vulgar Latin or Sermo Vulgaris ("common speech") is a generic term for the "nonstandard" (as opposed to "classical") sociolects of Latin from which the Romance languages developed. Works written in Latin during classical times used Classical Latin rather than Vulgar Latin, with very few exceptions (most notably sections of Gaius Petronius' "Satyricon"). Because of its nonstandard nature, Vulgar Latin had no official orthography. Vulgar Latin is sometimes also called colloquial Latin, or Common Romance (particularly in the late stage). In Renaissance Latin, Vulgar Latin was called "vulgare Latinum" or "Latinum vulgare."  - Old French (', ', ""; Modern French ) was the Gallo-Romance dialect continuum spoken from the 9th century to the 14th century.  In the 14th century, these dialects came to be collectively known as the "langues d'oïl", contrasting with the "langue d'oc" or Occitan language in the south of France. The mid-14th century is taken as the transitional period to Middle French, the language of the French Renaissance, specifically based on the dialect of the Île-de-France region.  - Music is an art form and cultural activity whose medium is sound and silence, which exist in time. The common elements of music are pitch (which governs melody and harmony), rhythm (and its associated concepts tempo, meter, and articulation), dynamics (loudness and softness), and the sonic qualities of timbre and texture (which are sometimes termed the "color" of a musical sound). Different styles or types of music may emphasize, de-emphasize or omit some of these elements. Music is performed with a vast range of instruments and vocal techniques ranging from singing to rapping; there are solely instrumental pieces, solely vocal pieces (such as songs without instrumental accompaniment) and pieces that combine singing and instruments. The word derives from Greek  ("mousike"; "art of the Muses"). In its most general form, the activities describing music as an art form include the production of works of music (songs, tunes, symphonies, and so on), the criticism of music, the study of the history of music, and the aesthetic examination of music. Ancient Greek and Indian philosophers defined music as tones ordered horizontally as melodies and vertically as harmonies. Common sayings such as "the harmony of the spheres" and "it is music to my ears" point to the notion that music is often ordered and pleasant to listen to. However, 20th-century composer John Cage thought that any sound can be music, saying, for example, "There is no noise, only sound."  - A song, most broadly, is a single (and often standalone) work of music that is typically intended to be sung by the human voice with distinct and fixed pitches and patterns using sound and silence and a variety of forms that often include the repetition of sections. Written words created specifically for music or for which music is specifically created, are called lyrics. If a pre-existing poem is set to composed music in classical music it is an art song. Songs that are sung on repeated pitches without distinct contours and patterns that rise and fall are called chants. Songs in a simple style that are learned informally are often referred to as folk songs. Songs that are composed for professional singers who sell their recordings or live shows to the mass market are called popular songs. These songs, which have broad appeal, are often composed by professional songwriters, composers and lyricists. Art songs are composed by trained classical composers for concert or recital performances. Songs are performed live and recorded on audio or video (or in some, cases, a song may be performed live and simultaneously recorded). Songs may also appear in plays, musical theatre, stage shows of any form, and within operas.  - A chansonnier (, Galician and , ) is a manuscript or printed book which contains a collection of chansons, or polyphonic and monophonic settings of songs, hence literally "song-books," although some manuscripts are so called even though they preserve the text but not the music (for example, the Cancioneiro da Vaticana and Cancioneiro da Biblioteca Nacional, which contain the bulk of Galician-Portuguese lyric). The most important chansonniers contain lyrics, poems and songs of the troubadours and trouvères of the Middle Ages. Prior to 1420, many song-books contained both sacred and secular music, one exception being those containing the work of Guillaume de Machaut. Around 1420, sacred and secular music was segregated into separate sources, with large choirbooks containing sacred music, and smaller chansonniers for more private use by the privileged. Chansonniers were compiled primarily in France, but also in Italy, Germany and in the Iberian peninsula.  - A villanelle (also known as "villanesque") is a nineteen-line poetic form consisting of five tercets followed by a quatrain. There are two refrains and two repeating rhymes, with the first and third line of the first tercet repeated alternately until the last stanza, which includes both repeated lines. The villanelle is an example of a fixed verse form. The word derives from Latin, then Italian, and is related to the initial subject of the form being the pastoral.  - The Renaissance was a period in European history, from the 14th to the 17th century, regarded as the cultural bridge between the Middle Ages and modern history. It started as a cultural movement in Italy in the Late Medieval period and later spread to the rest of Europe, marking the beginning of the Early Modern Age.  - A virelai is a form of medieval French verse used often in poetry and music. It is one of the three "formes fixes" (the others were the ballade and the rondeau) and was one of the most common verse forms set to music in Europe from the late thirteenth to the fifteenth centuries.    Given the paragraphs above, decide what entity has the relation 'subclass of' with 'poem'.
Answer:
formes fixes