Question: Were Douchan Gersi and Serge de Poligny both authors?

Context paragraphs:
Serge de Poligny: Serge de Poligny (1903–1983) was a French screenwriter and film director.

Return to Paradise (1935 film): Return to Paradise (French: Retour au paradis) is a 1935 French film directed by Serge de Poligny and starring Claude Dauphin, Mary Morgan and Marcel André.  The film's sets were designed by Pierre Schild.

The Fatted Calf: The Fatted Calf (French: Le veau gras) is a 1939 French comedy film directed by Serge de Poligny and starring Elvire Popesco, André Lefaur and Armand Bernard.  It is based on a play by Bernard Zimmer.  The film's sets were designed by Jacques Colombier and Robert Gys

The Phantom Baron: The Phantom Baron (French:Le baron fantôme) is a 1943 French drama film directed by Serge de Poligny and starring André Lefaur, Odette Joyeux and Jany Holt.

Explore (TV series): Explore was a 1980s PBS TV show based upon the film footage filmed by explorer Douchan Gersi over the previous 20 years.  The show was hosted by popular actor James Coburn.

Aces of the Turf: Aces of the Turf (French: Les as du turf) is a 1932 French comedy sports film directed by Serge de Poligny and starring Paul Pauley, Alexandre Dréan and Josyane.  It was made at Joinville Studios by the French subsidiary of Paramount Pictures.  In 1935 it was released in the United States with the alternative title of Racetrack Winners.

Thirst of Men: Thirst of Men (French: La soif des hommes) is a 1950 French historical drama film directed by  Serge de Poligny and starring  Georges Marchal, Dany Robin and Andrée Clément.  It was filmed and set in French Algeria.

You Will Be My Wife: You Will Be My Wife (French: Vous serez ma femme) is a 1932 German comedy film directed by Carl Boese, Serge de Poligny and Heinz Hille and starring Alice Field, Roger Tréville and Lucien Baroux.  It is the French-language version of UFA's "The Cheeky Devil".

The Star of Valencia: The Star of Valencia (German: Der Stern von Valencia ) is a 1933 German drama film directed by Alfred Zeisler and starring Liane Haid, Peter Erkelenz and Ossi Oswalda.  It was made in Mallorca, at the same time as a French-language version "L'étoile de Valencia" directed by Serge de Poligny.

Douchan Gersi: Douchan Gersi (1947–2015) was a Slovak-born, Belgium-raised, Bali-based adventurer, documentary filmmaker, author and actor, producer/star with actor James Coburn of "Explore", a PBS mini-series.  He is the author of numerous books including "Faces in the Smoke: An Eyewitness Experience of Voodoo, Shamanism, Psychic Healing, and Other Amazing Human Powers" and "Explorer".

Supporting paragraphs: Douchan Gersi Serge de Poligny
Answer: no