The alternative is my own archives, state archives, books of those years, reports on exhibitions, population census, advertisements, death dates, research, knowledge exchange with researchers and a lot of work)))
If Postnikova had thoroughly investigated each stamp, she would have written her book in our time.))) If there are hundreds of errors in the book, then why should I trust it? She did an important thing, but this is not enough for my attributions. The masters could change their last name, go to another factory, and then return, have the same initials, etc. Why do I need to know if there is some kind of master's mark in Postnikova's book, if I can look at the sources of those years myself?
ИН или НБ. The master could change his mark at least every year. Some did so.The period of the second kokoshnik is almost 20 years.
I do not use Postnikova's book except for some provincial cities. Sometimes I take note of information from Ivanov or Skurlov, which contains specific information or documents. For example, when the information contains a specific presentation of jewelry by the master to the assay chamber.