I'm pretty sure this is a Division 13 Specias, N. � medioluteus

Taken from the link below, there are numerous Common Names
Common Name(s):

"April Beauty", "Cemetery Ladies", "Loving Couples", "Primrose Peerless", "Twin Sisters"

There are also numerous synonyms:
N. albus Miller; N. x biflorus Curtis; N. cothurnalis Salisbury; N. dianthos Haworth; N. x grenieri Richter; N. loretii Rouy; N. tazetta-poeticus Grenier & Godron; N. triflorus Haworth

When sold, I think it is most commonly called Twin Sisters.

Where did you get it or do you know? Rescued from an old site?

chemocurl...aka Sue

Here is a link that might be useful: N. x medioluteus

Thank you so much! That is very helpful :)

You're welcome.