Leonid Konstantinovich Ramzin (Russian: Леони́д Константи́нович Рамзи́н ) (1887–1948) was a Soviet thermal engineer, and the inventor of a type of flow-through boiler known as the straight-flow boiler, or Ramzin boiler.
 He was a laureate of the Stalin Prize First-Class, which he received in 1943.
The leftover hash lemma is a lemma in cryptography first stated by Russell Impagliazzo, Leonid Levin, and Michael Luby.
Phthinosaurus is an extinct genus of therapsid from the Middle Permian of Russia.
 The type species Phthinosaurus borrisiaki was named by Soviet paleontologist Ivan Yefremov in 1940 on the basis of an isolated lower jaw.
 Because this jaw provides few distinguishing characteristics, the evolutionary relationships of "Phthinosaurus" are poorly known.
 Yefremov named the family Phthinosuchidae in 1954 to include "Phthinosaurus" and the newly named "Phthinosuchus", which was described on the basis of a crushed partial skull.
 American paleontologist Everett C. Olson placed both of these therapsids in the larger infraorder Phthinosuchia in 1961.
 In 1974 Leonid Tatarinov named the family Phthinosauridae to include "Phthinosaurus" alone, retaining "Phthinosuchus" within Phthinosuchidae.
Kate Dillon Levin (born March 2, 1974 in Washington D.C.) is an American model, activist and actress.
 She is best known for her work as a plus-size model where she appeared in multiple editorials in fashion magazines, appeared in cosmetics, plus-size, and designer campaigns, worked with top photographers on campaigns and in editorials and appeared in many mass media outlets.
 She was the first plus-size model to appear in U.S. Vogue and was the first plus-size model to appear in a Gucci campaign.
 Dillon has also been involved with many non-profit organizations, and is an advocate for eating disorder awareness and treatment, sustainability, global poverty reduction and social justice.
 She received her bachelor's degree in political science and international studies from University of St. Thomas and master's degree in international development from Harvard University's John F. Kennedy School of Government.
 Dillon was briefly married to Gabe Levin.
 During the marriage they had a son.
Anthony Frederick Levin (born June 6, 1946) is an American musician and composer, specializing in electric bass, Chapman Stick and upright bass.
 He also sings and plays synthesizer.
 Levin is best known for his work with King Crimson and Peter Gabriel.
 He was also a member of Liquid Tension Experiment, Bruford Levin Upper Extremities, ProjeKct One, and ProjeKct Four.
 He has led his own band, Stick Men.
Gabriel Levin (Born 1948, Paris) is a poet, translator and essayist.
 He lives in Jerusalem with his wife and children.
 Levin is one of the founding editors of Ibis Editions, a small non-profit press devoted to the publication of the literature of the Levant, and serves as its Editor-at-large.
 Levin's work has appeared in numerous literary magazines, including PN Review, The Times Literary Supplement, the Chicago Review, Raritan and Parnassus.
"To these Dark Steps", a volume written in response to operation "Cast Lead" (2008), was set by British composer Alexander Goehr for tenor, children's choir, and ensemble and premiered September 2012 at the CBSO Centre in Birmingham.
 Levin is the son of the American novelist Meyer Levin (best known for "Compulsion", the first "non-fiction novel") and French novelist Tereska Torres.
Leonid Anatolievich Levin ( ; Russian: Леони́д Анато́льевич Ле́вин ; Ukrainian: Леоні́д Анато́лійович Ле́він ; born November 2, 1948) is a Soviet-American computer scientist.
Pavel Samuilovich Urysohn (Па́вел Самуи́лович Урысо́н ) (February 3, 1898 – August 17, 1924) was a Soviet mathematician of Jewish origin who is best known for his contributions in dimension theory, and for developing Urysohn's Metrization Theorem and Urysohn's Lemma, both of which are fundamental results in topology.
 His name is also commemorated in the terms Urysohn universal space, Fréchet–Urysohn space, Menger–Urysohn dimension and Urysohn integral equation.
 He and Pavel Alexandrov formulated the modern definition of compactness in 1923.
Meyer Levin (October 7, 1905 – July 9, 1981) was an American novelist.
 Perhaps best known for his work on the Leopold and Loeb case, Levin worked as a journalist (for the "Chicago Daily News" and, from 1933–39, as an editor for "Esquire").
Leonid Bunimovich is a Soviet and American mathematician, who specializes in dynamical systems.
 He is known for discovery of a fundamental mechanism of chaos (hyperbolicity) in Dynamical systems, which is called mechanism of defocusing.
 The most famous class of chaotic dynamical systems of this type Dynamical billiards are focusing chaotic billiards (e.g., the "Bunimovich stadium","Bunimovich flowers", etc.).
 More recently he introduced so called Bunimovich mushrooms, which are visual examples of billiards with mixed regular and chaotic dynamics.
 In many labs over the world were built experimental devices in the form of various Bunimovich billiards.
 He received bachelor's degree in 1967 and PhD in 1973 from the University of Moscow.
 His thesis adviser was Yakov G. Sinai.
 In 1986 he was awarded Doctor of Sciences degree in "Theoretical and Mathematical Physics".

Question: Were Pavel Urysohn and Leonid Levin known for the same type of work?
Answer: no