Hellstern was name-checked in the novels of both Nancy Mitford and F. Scott Fitzgerald and if a flapper had money to burn, this particular shoe emporium was where she would go to salivate over their silver kid slippers and blood-red suede bar shoes. 
Caroline Cox
Vintage Shoes (Carlton Books, 2008)

1948 | Hellstern & Sons patent
Source: INPI (Institute National de la Propriété Industrielle - France)

Nancy Mitford and Francis Scott Fitzgerald? COOL!

Only it's not true. On both counts, we checked. Now, why everyone would write such things?

- too many pictures and not enough text?

- hearsay?

- crosschecking is waste of time?

- all of the above?

Decline of Western civilization.

1922 | Hellstern & Sons patent
Source: INPI (Institute National de la Propriété Industrielle - France)

And then some:

Their premises were in the Place Vendome and their clientele included society women, stage performers and royalty. They are mentioned in Proust's novel. 
Source: Fine Arts Museums Of San Francisco

A fit description for Hellstern & Sons, but it goes without saying that dear old Proust didn't mention them. Ever. You know the end is near if even museums fail you.

There are however a few novels that mention Hellstern and Sons like "The Shoe Queen" by Anna Davis (but they - the Hellstern shoes - are mentioned in passing as the queen shoes are Perugias); or "Man In A Hurry", a 1914 French classic by Paul Morand.

1920 - 1928 | Hellstern And Sons
© Romans; Musée international de la Chaussure
Photograph Christophe Villard

Noteworthy is the biography of Gerald and Sarah Murphy:

She (Sarah Murphy) told the Hemingways that she was pining to go to Paris in September: 
I want new clothes & new ideas (in order named) & Hellstern shoes & perfumery & trick hats, & linge [underwear], not to mention the eve. dress & to sit hours with Léger & his friends in cafés, & haunt rue la Boétie, & see every good new play & all music if any, & be back here in about three days & eleven hrs. twenty-seven mins. . . .  
Amanda Vaill
Everybody Was So Young: Gerald and Sara Murphy, A Lost Generation Love Story

The Murphys were a wealthy couple of American expats in Paris whose circle of friends included John Dos Passos, Ferdinand Léger, Hemingway, Picasso (who even portrayed Sara Murphy - true story) and Francis Scott Fitzgerald who used a fictionalized portrait of the Murphys in the novel "Tender Is The Night".

And that is the only link between Hellstern and Francis Scott Fitzgerald.

Hellstern & Sons | Insole label
© Romans; Musée international de la Chaussure