your admiration for those watches! This ref. 42666.57.71 "equation lunaire" from the equation "ligne technique" line is another outstanding piece of GPs portfolio from about 1985-1990 with moonphase indications for the north and the south hemisphere at the same time! I'm most impressed by this combination of quartz base movement on the highest level and sophisticated mechanical complication and enamel dial, the batteries in those watches have a power reserve of more than 5 years (for the ladies watches about 2 years +). One day I would like to lay hands on a perpetual calendar watch of this line. But you have to find one!
congrats and greetings, Alex from Germany