Complex sentence: The Mortensen-Pissarides model that resulted from this paper has been exceptionally influential in modern macroeconomics, and that in one of other of its extensions or variations, today is part of the core of most graduate economics curricula throughout the world.
Split into simpler sentences: The Mortensen-Pissarides model that resulted from this paper has been exceptionally influential in modern macroeconomics. In one or another of its extensions or variations, today it is part of the core of most graduate economics curricula throughout the world.