Interesting note from one of the Hindi Granthas about Shree PanchaRatra.
"Shree Sattvata-Samhita" says about 3-fold stages of Bhagavan Shree Vasudeva (Para, Vyuha, Vibhava), while "Shree Ahirbudhnya-Samhita", for example, says about classic 5-fold division (Para, Vyuha, Vibhava, Antaryami, Archa).
And I will add from myself - Our Precious Ishwari Shreemati MahaLakshmi-Devi in "Shree Lakshmi-Tantra" says about 5-fold division too.
The difference is not very crucial, because "Shree Sattvata-Samhita" actually says about 5-fold division but in compact form and because all the Granthas of "Shree PanchaRatra" are mutually supportive and complementary, so 3-folded Siddhanta from "Shree Sattvata-Samhita" is being expanded up to 5-fold division in other Granthas of "Shree PanchaRatra" (the above-mentioned "Shree Lakshmi-Tantra", "Shree Ahirbudhnya-Samhita" and others).
Trividha-cite from "Shree Satvata-Samhita" (1.24) is very simpe and beautiful, I have transliterated into ITRANS:
त्रिविधेन प्रकारेण परमं ब्रह्म शाश्वतं |
आराधयन्ति ये तेषां रागस्तिष्ठति दुरतः | |
trividhena prakAreNa paramaM brahma shAshvataM |
ArAdhayanti ye teShAM rAgastiShThati durataH |