Corsa has the hidden fifth chainring bolt under the arm, where the pin is on the outer ring. All of the rings are 5 bolt. In the picture above of the two ring sets you can see that I lined up the pin, and the bolts are out of phase with respect to the pin/crank arm.

I have swapped my rings just to prove you can. Bolt Circle Diameter (BCD) is the critical measurement. Starting with the "High Art era" as I call it, Campy has used a 135 BCD. They still do. The major change was to move the two rings closer together. You should be able to mount modern rings on classic Chorus and Corsa cranks (depending on pin issues). (See also: Chainrings - Branford Bike - Seattle/Bellevue - Campagnolo Pro Shop)
Note that the latest (2015) models of Record have irregular bolt hole spacing - which won't work. But I think the lower lines and 2014 and earlier should be 135 BCD.
BCD is difficult to measure, but you can see from that link that the bolt center to bolt center is just under 8cm. Easy to measure.

Super Record (and other groups) of the '70s / '80s vintage have a different ring design (144 BCD)

I have a 42/53 set on Chorus, and currently a 42/50 on Corsa. I have a spare 39 around here somewhere. I'm hoping to get a 53 Corsa, but I'm waiting to see if I can get a good deal on the 'bay.
I have an Eddy Merckx bike with what looks like slightly later Chorus/Athena drive train (possibly 1992-ish). Looks like it might be a 39/53 set of rings. My friend currently has that machine, when I pick it up I'll be parting it out. If you are interested in the rings, let me know.
I also have a MTB at my parent's house with a complete 2014 Veloce 10x3 drive train, I'll check the BCD of the outer ring.

~Monkey~