Professor Proton said
I should call him Arthur.
The Big Bang Theory Season 6, Episode 22
that being on
the Professor Proton show
The Big Bang Theory Season 11, Episode 15
... a.k.a. Professor Proton,
will be in our apartment?
The Big Bang Theory Season 6, Episode 22
Professor Proton,
it's an honor to meet you.
The Big Bang Theory Season 6, Episode 22
I know you have strong feelings
about Professor Proton,
The Big Bang Theory Season 11, Episode 15