As said in page 24, the Volvo Sarakakis Articulated variant, nicknamed "Dinosaur". It was a original Sarakakis design, not from Volvo, as Sarakakis claimed, but I am sure that there was a Volvo touch into it. They had some issues with the link at first years, but fixed. I read somewhere that Sarakakis bought the patent of an Austrian (or Swiss) articulate link and adapted it into his SB756 bus.
Not sure about the red/blue exact tone, but pretty close (I think), photos available are unfortunately not very helpful.
A short ride on a historic SB756 in Athens:
https://www.youtube.com/watch?v=v8iXk0nOMwQ
P.S Edited also the 12m SB56 in page 24 with some corrections. In the video, just do not care about talk, listen the wonderful sound of Volvo THD102, perhaps the best sounding Volvo diesel ever.