Researching London fashion houses

Hello
I'm carrying out family research and hoping to find information about my late mother, who worked for two well known London fashion houses in the 1920s and 1930s.
Her first position was as an apprentice at Bradleys of 1 Chepstow Place, London W2.
She later moved to The White House of 51 New Bond Street.
Sha also did some photographic modelling via the Bassano Studio. I have viewed hundreds of negatives but find it difficult to identify definitely which are of her.
In about 1948, she went to Johannesburg to open a branch of The White House.
So I wonder where to pursue my researches - if there are archives that might hold more information. Any suggestions would be gratefully received !

 

What was her name when she worked at those places? I will see if I can find anything about her then.

 

Many thanks for the two replies.
My mother's name was Lilian Richens Baxter.
On the Bassano studio photos, I have looked through a large number of photos on the archive. The problem is that they do not name the model, only the product being promoted. I found one photo that I thought could be her - she was wearing a signet ring and I really want to see that in close up as it might prove conclusive.
If that is her, then she modelled for a knitwear company. I contacted them but they had no record of the names of their models.
So frustrating !