Question: Were Joris Ivens and Walter Lang in the same industry?

Context articles: Our Russian Front
Misère au Borinage
Walter Lang
The Song of the Rivers
Rain (1929 film)
The Seine Meets Paris
A Tale of the Wind
Mannus Franken
Freetime Machos
Joris Ivens

Our Russian Front is a 1942 American documentary film directed by Joris Ivens and Lewis Milestone, and narrated by Walter Huston to promote support for the Soviet Union's war effort.
Misère au Borinage (French, literally "Poverty in the Borinage"), also known as Borinage, was a 1934 Belgian documentary film directed by Henri Storck and Joris Ivens.
 Produced during the Great Depression, the film has a strongly socialist theme, covering the poor living conditions of the workers and coal miners of the Borinage region of Belgium.
 It is considered a classic work of political cinema and has been described as "one of the most important references in the documentary genre".
Walter Lang (August 10, 1896 – February 7, 1972) was an American film director.
The Song of the Rivers (German: Das Lied der Ströme ) is a 1954 documentary film production by the East Germany's Deutsche Film-Aktiengesellschaft (DEFA).
 Dutch filmmaker Joris Ivens was the leading director.
 The sprawling film celebrates international workers movements along six major rivers: the Volga, Mississippi, Ganges, Nile, Amazon and the Yangtze.
 Shot in many countries by different film crews, and later edited by Ivens, Song of the Rivers begins with a lyrical montage of landscapes and laborers and proceeds to glorify labor and modern industrial machinery.
 The musical score is by Dmitri Shostakovich, with lyrics written by Berthold Brecht, and songs performed by German communism's star Ernst Busch and famous American actor, singer and activist Paul Robeson who also narrates.
 Song of the Rivers is an ode to "international solidarity".
Rain (Dutch: Regen ) is a 1929 Dutch short documentary film directed by Mannus Franken and Joris Ivens.
 It premiered on December 14, 1929, in the Amsterdam Filmliga’s theater, De Uitkijk.
The Seine Meets Paris (French: La Seine a rencontré Paris ) is a 1957 French short documentary film directed by Joris Ivens from a screenplay by Jacques Prévert.
 Told from the perspective of a boat trip through the city, it features scenes of daily life along the river.
 The film won the short film Palme d'Or at the 1958 Cannes Film Festival.
A Tale of the Wind (French: Une Histoire de vent ) is a 1988 French film directed by Joris Ivens and Marceline Loridan.
 It is also known as A Wind Story.
 It stars Ivens as he travels in China and tries to capture winds on film, while he reflects on his life and career.
 The film blends real and fictional elements; it ranges from documentary footage to fantastical dream sequences and Peking opera.
 It was Ivens' last film.
Mannus Franken (2 February 1899 – 1 August 1953) was a Dutch filmmaker who played an important role in the development of Indonesian cinema.
 He made his debut as a writer before working with Joris Ivens in producing two documentary films.
 In 1934 he was called to the Dutch East Indies by Albert Balink to help with the production of "Pareh" (1936).
 Franken stayed in the Indies until before World War II, making newsreels.
 After the war he returned to the country and continued this work.
 In 1949 Franken returned to the Netherlands, where he made another film before his death.
Freetime Machos is a Finnish documentary film about the bromance of two players in world's most northerly rugby club called OYUS Rugby based in Oulu, Finland.
 The film is directed by Mika Ronkainen and it had its world premiere at the Joris Ivens Competition of IDFA in November 2009.
 The film got its North American premiere at Tribeca Film Festival in April 2010.
 It was also part of the Edinburgh International Film Festival in June 2010.
Georg Henri Anton "Joris" Ivens (18 November 1898 – 28 June 1989) was a Dutch documentary filmmaker.
 Among the notable films he directed or co-directed are "A Tale of the Wind", "The Spanish Earth", "Rain", "...A Valparaiso", "Misère au Borinage" ("Borinage"), "", "The Seine Meets Paris", "Far from Vietnam", "Pour le Mistral" and "How Yukong Moved the Mountains".