Question: Are Monta Bell and Mack Sennett both directors?

Context articles: The Snob (1924 film)
Mack at It Again
Blue of the Night
Sing, Bing, Sing
Monta Bell
At Coney Island
The Worst Woman in Paris?
Mack Sennett
The Bellamy Trial
Girl Crazy (1929 film)

The Snob was a 1924 American silent drama film directed by Monta Bell.
 The film starred Norma Shearer and John Gilbert prior to their stardom, together with Phyllis Haver, Conrad Nagel and Hedda Hopper.
 The film was written by Monta Bell, and was based on the novel "The Snob: The Story of a Marriage" by Helen Reimensnyder Martin.
 The film is now considered lost.
Mack at It Again is a 1914 short comedy film starring Mabel Normand and Mack Sennett.
 Mack Sennett also directed the film.
 The picture was produced by Sennett's Keystone Film Company and distributed by Mutual Film.
Blue of the Night is a 1932 Mack Sennett Star Comedy (No.
 S3628) starring Bing Crosby and directed by Leslie Pearce.
 This was the last of the six short films Crosby made for Mack Sennett and which helped launch his career as a solo performer.
Sing, Bing, Sing is a 1932 Mack Sennett Star Comedy (No.
 S3627) starring Bing Crosby and directed by Babe Stafford.
 This was the fifth of the six short films Crosby made for Mack Sennett and which helped launch his career as a solo performer.
Monta Bell (February 5, 1891 – February 4, 1958) was an American film director, producer and screenwriter.
At Coney Island, also known as Cohen at Coney Island, is a 1912 American short silent comedy starring Mack Sennett, Mabel Normand, and Ford Sterling.
 Sennett also directed and produced the film.
 According to the book "Mack Sennett's Fun Factory: A History and Filmography of His Studio and His Keystone and Mack Sennett Comedies, with Biographies of Players and Personnel", Sennett claimed this was the first Keystone Studios production, shot on location at Coney Island on July 4, 1912.
 It was the eleventh Keystone film released, on a split-reel with "A Grocery Clerk's Romance".
The Worst Woman in Paris?
 is a 1933 American drama film directed by Monta Bell and written by Monta Bell and Marion Dix.
 The film stars Benita Hume, Adolphe Menjou, Harvey Stephens, Helen Chandler, Margaret Seddon and Adele St. Mauer.
 The film was released on October 20, 1933, by Fox Film Corporation.
Mack Sennett (born Michael Sinnott; January 17, 1880 – November 5, 1960) was a Canadian-born American director and actor and was known as an innovator of slapstick comedy in film.
 During his lifetime he was known at times as the "King of Comedy".
 His short "Wrestling Swordfish" was awarded the Academy Award for Best Live Action Short Film in 1932 and he earned an Academy Honorary Award in 1937.
The Bellamy Trial is a 1929 American drama film directed by Monta Bell and written by Monta Bell and Joseph Farnham.
 The film stars Leatrice Joy, Betty Bronson, Edward J. Nugent, George Barraud and Margaret Livingston.
 The film was released on January 23, 1929, by Metro-Goldwyn-Mayer.
Girl Crazy was a 1929 comedy film directed by Mack Sennett and starring Andy Clyde as "a girl-crazy sexagenarian".
 The film's story is credited to Hampton Del Ruth, Alfred J. Goulding, Harry McCoy, Earle Rodney, and Mack Sennett.