Opens with the quote, "Ah! It was colder than ice; it penetrated to his very heart." This is from the fairy tale The Snow Queen by Hans Christian Andersen.
The location of the second attack is "route 4, marker 17". This is probably part of the episode-number running gag of the show, incorporating the episode numbers in the actual episodes, being episode 17 in season 4.
"Hibernaculum" is the Latin nominative (and vocative) case noun for 'winter residence', or 'place of hibernation'.
Kuh-Newt is a correct, authentic pronunciation of the name Knute. It's not mispronounced in this episode.
Esther Blake is frozen solid; Nick says the bite on her trapezius looks like frostbite. Given that frostbite is when skin and underlying tissue gets frozen, Blake's entire body is frostbitten.