One verse

Srimad Bhagavatam 3.11.22

3.11.22

त्रिलोक्या युगसाहस्रं बहिराब्रह्मणो दिनम् । तावत्येव निशा तात यन्निमीलति विश्वसृक् ॥ २२ ॥

tri-lokya yuga-sahasram bahir abrahmano dinam tavaty eva nisa tata yan nimilati visva-srk

tri-lokyah
of the three worlds
yuga
the four yugas
sahasram
one thousand
bahih
outside of
abrahmanah
up to Brahmaloka
dinam
is a day
tavati
a similar (period)
eva
certainly
nisa
is night
tata
O dear one
yat
because
nimilati
goes to sleep
visva-srk
Brahma.

Outside of the three planeary systems (Svarga, Martya and Patala), the four yugas multiplied by one thousand comprise one day on the planet of Brahma. A similar period comprises a night of Brahma, in which the creator of the universe goes to sleep.