Question: Which screenwriter is French, Roger Vadim or Robert Z. Leonard?

Context articles: Nathalie Vadim
Roger Vadim
The Long Teeth
And God Created Woman (1956 film)
Robert Z. Leonard
Don Juan, or If Don Juan Were a Woman
Pretty Maids All in a Row
Christian Vadim
The Night Heaven Fell
And God Created Woman (1988 film)

Nathalie Vadim (born 1958) is the daughter of Roger Vadim and actress Annette Stroyberg.
 While her father was married to Oscar-winning actor Jane Fonda, Vadim's family would go on vacations that lasted several weeks or a month to Saint-Tropez or the Arcachon Bay and spend time in the mountains or on the water.
 In May 1987, Vadim worked as second assistant director on her father's remake film "And God Created Woman".
 Like her father, she has been involved in directing many films.
Roger Vadim Plemiannikov (] ; 26 January 1928 – 11 February 2000) was a French screenwriter, film director and producer, as well as an author, artist and occasional actor.
 His best-known works are visually lavish films with erotic qualities, such as "And God Created Woman" (1956), "Barbarella" (1968), and "Pretty Maids All in a Row" (1971).
The Long Teeth (original title "Les Dents longues") is a French comedy drama film from 1953, directed by Daniel Gélin, written by Michel Audiard.
 It features Danièle Delorme, Louis de Funès, Roger Vadim and Brigitte Bardot.
 The story is based on Jacques Robert's novel "Les dents longues".
And God Created Woman (French: "Et Dieu… créa la femme" ) (1956) is a French drama film directed by Roger Vadim and starring Brigitte Bardot.
 Though not her first film, it is widely recognized as the vehicle that launched Bardot into the public spotlight and immediately created her "sex kitten" persona, making her an overnight sensation.
Robert Zigler Leonard (October 7, 1889 – August 27, 1968) was an American film director, actor, producer, and screenwriter.
Don Juan, or If Don Juan Were a Woman (French: Don Juan ou Si Don Juan était une femme... ) is a 1973 French-Italian drama film by Roger Vadim.
 It sees Vadim reunite with his leading lady and ex-wife Brigitte Bardot for their fifth film together.
 Bardot achieved international stardom and Vadim got his break when he directed her in the 1956 sensation, "And God Created Woman".
 It was her second to last film before retiring.
Pretty Maids All in a Row is an American mystery film that is part dark comedy, part murder mystery.
 Starring Rock Hudson alongside Angie Dickinson, it was released on April 28, 1971.
 Roger Vadim directed the film, which Gene Roddenberry produced, having dramatized a 1968 novel written by Francis Pollini into the screenplay from which Vadim worked.
 This was Roddenberry's only feature film writing credit.
Christian Vadim (born June 18, 1963) is a French actor.
 He is the son of actress Catherine Deneuve and director Roger Vadim.
The Night Heaven Fell ("Les bijoutiers du claire de lune") is a Eastmancolor 1958 French-Italian film directed by Roger Vadim.
 Vadim had already acquired international fame with his daring debut "And God Created Woman" (1956).
 Like its predecessor, "The Night Heaven Fell" explored the exuberant sensuality of Brigitte Bardot, who was Vadim's wife at the time.
And God Created Woman is a 1988 film directed by Roger Vadim and starring Rebecca De Mornay and Vincent Spano.
 It has the same title as the 1956 French film "Et Dieu… créa la femme" ("And God created woman") starring Brigitte Bardot, also directed by Vadim, but has a completely different story.