Early 70s scifi novel about underground men and women, caste is decided by the colour of your poncho, and everyone eats mouldy grainEarly 70s scifi novel about underground persons, caste is decided by the color of your poncho, and everybody eats mouldy grainإحْتِرافي، مُحْتَرِفحِرَفي، عالي المُسْتَوىحِرَ�