The name "Nordic" confuses me, too, when the other sets in the series are called "May," "October," and November." I'm fairly sure of the identification, though, as I'm relying on The Kosta Boda Book of Glass from 1986 (which I'd recommend if you're interested in this type of glass). Looking at the catalogue numbers assigned to each set by Kosta Boda, "Nordic" has the lowest number, which I'm presuming is the earliest. I wonder if they introduced "Nordic," found it successful, and so started the month series. "October" seems to be the most common, followed by "May." I've never actually seen an example of "Nordic" outside the the Kosta Boda book.
On the subject of the Pina books, I've just finished recommending them to a person who was looking for the best general books on Scandinavian glass. I'd stand by that recommendation as this is the first minor error I've found in the two books. For a while there was a bit of criticism of Pina in some postings, mainly for her other books. There are some errors in Fifties Glass but she corrected them in Italian Glass and her books on Seguso and Toso are pretty good. There are some other good books on Scandinavian glass, but they are either very specialized or deal in very expensive glass, which is generally beyond my means. Pina's great strength is that she identifies glass that you are likely to come across. A part of of me would like them (the two Scandinavian books) to be more comprehensive, but then they would be huge and much more expensive. Pina and Vigier do a pretty good job of selecting the stuff you're likely to come across.
Elaine, if you got it for a tenner (on eBay I'm presuming), you did very well. I missed it completely and I would have bid more than a tenner! Greetings to Central Scotland, BTW, as I was born in Edinburgh and raised in Galashiels.