Astanga Hrudaya
पञ्चकेष्वेकमेवाम्लो मधुरः पञ्च सेवते। द्रव्यमेकं षडास्वादमसंयुक्ताश्च षड्रसाः॥४२॥
In the combination of 5 rasas it will be 1 with amla, 5 with svadu total 6 In the combination of all the 6 rasas it will be one Each rasa individually will be 6 Thus forming 63 combinations in total
english translation
paJcakeSvekamevAmlo madhuraH paJca sevate। dravyamekaM SaDAsvAdamasaMyuktAzca SaDrasAH॥42॥
hk transliteration by Sanscript