Devibhagavatapurana 7.35.31

7.35.31

sarvatejomayī sā tu suṣumnā vahnirūpiṇī |
tasyā madhye vicitrākhye icchājñānakriyātmakam ||

The inmost of Susumnâ is Vichtrâ or Chitrinî Bhûlingam nâdî (of the form of a cobweb) in the middle of which resides the Ichchâ (will), Jñâna (knowledge) and Kriyâ (action) S'aktîs, and resplendent like the Millions of Suns. Above Him is situated Hrîm, the Mâyâ Vîja Harâtmâ with "Ha" and Chandravindu repesenting the Sound (Nâda). Above this is the Flame, Kula Kundalinî (the Serpent Fire) of a red colour, and as it were, intoxicated. Outside Her is the Âdhâra Lotus of a yellow colour having a dimension of four digits and Comprising the four letters "va", "s'a", "sa", and "sa". The Yogis meditate on this. In its centre is the hexagonal space (Pîtham). This is called the Mûlâdhâra for it is the base and it supports all the six lotuses. Above it is the Svâdhisthâna Chakra, fiery and emitting lustre like diamond and with six petals representing the six letters "ba", "bha", "ma", "ya", "ra", "la". The word "Sva" means "Param Lingam" (superior Male Symbol). Therefore the sages call this "Svâdhisthân Chakram. Above it is situated the "Manipura Chakram" of the colour of lightning in clouds and very fiery; it comprises the ten Petals, comprising the 10 letters da, dha, na, ta, tha, da, dha, na, pa, pha. The lotus resembles a full blown pearl; hence it is "Manipadma." Visnu dwells here. Meditation here leads to the sight of Visnu, Above it is "Anâhata" Padma with the twelve petals representing, the twelve letters Ka, Kha, Gha, m###, (cha), (chha), (Ja), (Jha,) Îya, ta, and tha. In the middle is Bânalingam, resplendent like the Sun. This lotus emits the sound S'abda Brabma, without being struck; therefore it is called the Anâhata Lotus. This is the source of joy. Here dwalls Rudra, the Highest Person."