Question: A peck is an imperial and United States customary unit of dry volume, equivalent to 2 gallons or 8 dry quarts or 16 dry pints, despite being referenced in which well-known English-language nursery rhyme and well-known alliteration tongue-twister?

Context paragraphs:
Peter Piper: "Peter Piper" is an English-language nursery rhyme and well-known alliteration tongue-twister.  It has a Roud Folk Song Index number of 19745.

United States customary units: United States customary units are a system of measurements commonly used in the United States.  The United States customary system (USCS or USC) developed from English units which were in use in the British Empire before the U.S. became an independent country.  However, the United Kingdom's system of measures was overhauled in 1824 to create the imperial system, changing the definitions of some units.  Therefore, while many U.S. units are essentially similar to their Imperial counterparts, there are significant differences between the systems.  However, in the U.S. the term "imperial" is commonly used when one is referring to a U.S. customary unit.

Miles per hour: Miles per hour (abbreviated mph, MPH or mi/h) is an imperial and United States customary unit of speed expressing the number of statute miles covered in one hour.  Miles per hour is the standard unit for speed limits in the United States, the United Kingdom, Antigua & Barbuda and Puerto Rico, other nations use kilometres per hour.

Ser (unit): A ser is an obsolete unit of dry volume in India.  In 1871 it was defined as being exactly 1 litre (1.06 quarts).  After metrication in the mid-20th century, the unit became obsolete.

Cullishigay: A cullishigay is an obsolete unit of dry volume used on the Malabar coast of southern India approximately equal to 1.25 imperial bushels (44 litres).  It was a third of a mudi or moray, a larger unit of dry volume.  After metrification in the mid-20th century, the unit became obsolete.

Mots d'Heures: Mots D'Heures: Gousses, Rames: The D'Antin Manuscript ("Mother Goose's Rhymes"), published in 1967 by Luis d'Antin van Rooten is purportedly a collection of poems written in archaic French with learned glosses.  In fact, they are English-language nursery rhymes written homophonically as a nonsensical French text (with pseudo-scholarly explanatory footnotes); that is, as an English-to-French homophonic translation.  The result is not merely the English nursery rhyme but that nursery rhyme as it would sound if spoken in English by someone with a strong French accent.  Even the manuscript's title, when spoken aloud, sounds like "Mother Goose's Rhymes" with a strong French accent.

Peck: A peck is an imperial and United States customary unit of dry volume, equivalent to 2 gallons or 8 dry quarts or 16 dry pints (9.09 (UK) or 8.81 (US) liters).  Two pecks make a kenning (obsolete), and four pecks make a bushel.  Although the peck is no longer widely used, some produce, such as apples, is still often sold by the peck.  Despite being referenced in the well-known Peter Piper tongue twister, pickled peppers are so rarely sold by the peck that any association between pickled peppers and the peck unit of measurement is considered humorous in nature.

Bushel: A bushel (abbreviation: bsh.  or bu.)  is an imperial and US customary unit of weight or mass based upon an earlier measure of dry capacity.  The old bushel was equal to 2 kennings (obsolete), 4 pecks or 8 gallons and was used mostly for agricultural products such as wheat.  In modern usage, the volume is nominal, with bushels denoting a mass defined for each commodity differently.

Quart: The quart (abbreviation qt.)  is an English unit of volume equal to a quarter gallon.  It is divided into two pints or four cups. Historically, the exact size of the quart has varied with the different values of gallons over time and in reference to different commodities.  Presently, three kinds of quarts remain in use: the liquid quart and dry quart of the US customary system and the imperial quart of the British imperial system.  All are roughly equal to one metric liter.

Radical 68: Radical 68 meaning "dipper" is 1 of 34 Kangxi radicals (214 radicals total) composed of 4 strokes.  市斗, sometimes represented by 斗 alone, is also the symbol for a Chinese traditional measurement of dry volume equaling about 10 liters, which is ~18.16 pints, ~2.27 gallons, ~610.2 cubic inches, or ~0.3531 cubic feet.

Supporting paragraphs: Peck Peter Piper
Answer: Peter Piper