Easily look up PTS references in the Khuddaka Nikaya. (Or look up PTS references in the first four Nikayas ) The Khuddaka Nikaya is the fifth Nikaya known as Collection of Minor Texts , it consists of 15 to 18 books depending on tradition. I beleive, the original Pali Canon has 15 books while the Thai edition has 17 and the Burmese edition 18 books. These then have been arranged and numbered in a couple of different ways.
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Pali language grammar tutorials. Learn to read the Pali language for yourself.