One verse

Srimad Bhagavatam 12.6.46

12.6.46

ते परम्परया प्राप्तास्तत्तच्छिष्यैर्धृतव्रतै: । चतुर्युगेष्वथ व्यस्ता द्वापरादौ महर्षिभि: ॥ ४६ ॥

te paramparayā prāptās tat-tac-chiṣyair dhṛta-vrataiḥ catur-yugeṣv atha vyastā dvāparādau maharṣibhiḥ

te
these Vedas
paramparayā
by continuous disciplic succession
prāptāḥ
received
tat-tat
of each succeeding generation
śiṣyaiḥ
by the disciples
dhṛta-vrataiḥ
who were firm in their vows
catuḥ-yugeṣu
throughout the four ages
atha
then
vyastāḥ
were divided
dvāpara-ādau
at the end of the Dvāpara millennium
mahā-ṛṣibhiḥ
by great authorities

In this way, throughout the cycles of four ages, generation after generation of disciples — all firmly fixed in their spiritual vows — have received these Vedas by disciplic succession. At the end of each Dvāpara-yuga the Vedas are edited into separate divisions by eminent sages.