Whose work is credited with being the beginning of modern atomic theory?
Bohr and Sommerfield
We could have talked about them individually but they do not have individual existance.
The bohr model was revolutionary,developed on the grounds and the conclusions of the rutherford.
But it had many drawbacks ; For ex- It applied to only hydrogen like species.
But the Idea was extended by sommerfield,and he gave the idea of fine spectrum,and talked about the existence of subshells.
The idea of Subshells is the most biggest thing able to explain the chemistry of reactions and stability .
So ,i my opinion both are cumulative.