Harmonia Caelestis is a cycle of 55 sacred cantatas attributed to the Hungarian composer Paul I, 1st Prince Esterházy of Galántha (1635–1713) and published in 1711.
 They are in the Baroque style and incorporate traditional Hungarian and German melodies.
 Each of the cantatas consists of one movement.
 They are composed for solo voices (the majority for one solo voice, although there are some duets), choir, and orchestra (including violas, violone, harp, bassoon, theorba, violins, flutes, trumpets, organ, timpani).
Camilla de Rossi (fl.
 1707–1710) was an Italian composer.
 Several women are known to have composed music in Northern Italy and Austria during the period 1670 to 1725.
 Of those women, though there is no remaining biographical information, Camilla de Rossi by far has the most surviving works.
 The only known biographical detail about Camilla is her Roman citizenship.
 She always signed the title pages of her manuscripts as "Romana," or a woman of Roman descent.
 Rossi composed four oratorios for solo voices and orchestra, all of which were commissioned by Emperor Joseph I of Austria and were performed in the Imperial Chapel in Vienna.
The St Matthew Passion (German: "Matthäus-Passion" ), BWV 244, is a "Passion", a sacred oratorio written by Johann Sebastian Bach in 1727 for solo voices, double choir and double orchestra, with libretto by Picander (Christian Friedrich Henrici).
 It sets chapters and of the Gospel of Matthew (in the German translation of Martin Luther) to music, with interspersed chorales and arias.
 It is widely regarded as one of the masterpieces of classical sacred music.
 The original Latin title Passio Domini nostri J.C. secundum Evangelistam Matthæum translates to "The Passion of our Lord J[esus] C[hrist] according to the Evangelist Matthew".
A boy soprano is a young male singer with an unchanged voice in the soprano range.
By 2013 the drug discovery market had begun shifting from the single to the multi-target paradigm, of which Persomics’ technology is a part.
 Prior to that time, popular drug discovery efforts focused on identifying single drugs that fit into specific cellular targets; this came to be known as target-based screening (i.e. reverse pharmacology).
 The multi-target approach entails the understanding that, although one drug compound might fit into a single target, diseases are associated with complex biological processes, and often multiple cellular targets, which are more difficult to unlock.
 Today phenotypic screening is enjoying a significant resurgence as part of the portfolio of drug discovery strategies leveraged at most companies.
 This is because phenotypic screening products (such as those offered by Persomics) offer a potentially revolutionary approach to discerning multiple cellular targets as the basis for genetic disease.
The orchestral song (German "Orchesterlied ") is a late romantic genre of classical music for solo voices and orchestra.
Henry Holmes (7 November 18399 December 1905) was an English violinist, composer, and music educator.
 His compositional output includes a violin concerto, several works for solo violin, four symphonies, a concert overture, two sacred cantatas for solo voices, chorus, and orchestra, and other chamber and choral works.
Suzana Kostić (born December 31, 1961) is a Serbian conductor, music educator and music scholar.
 Her performance specialties are choral music and large-scale works for solo voices, chorus, and orchestra.
 She is also known for the premiere performances of works by contemporary Balkan composers.
"Das Glühwürmchen", known in English as "The Glow-Worm", is a song from Paul Lincke's 1902 operetta "Lysistrata", with German lyrics by Heinz Bolten-Backers.
 In the operetta, it is performed as a trio with three female solo voices singing alternately and the women's chorus joining in the refrain.
 Rhythmically, it is in the form of a gavotte.
 The song, with its familiar chorus, was translated into English and became an American popular song.
A Ceremony of Carols, Op. 28, is a choral piece by Benjamin Britten, scored for three-part treble chorus, solo voices, and harp.
 Written for Christmas, it consists of eleven movements, with text from "The English Galaxy of Shorter Poems", edited by Gerald Bullett; it is in Middle English.
 The piece was written in 1942 while Britten was at sea, going from the United States to England.

Question: What solo voices might fit for A Ceremony of Carols?
Answer: boy soprano