Śrīmad-Bhāgavatam 5.24.6
తతోఽధస్తాచ్ఛతయోజనాన్తర ఇయం పృథివీ యావద్ధంసభాసశ్యేనసుపర్ణాదయ: పతత్త్రిప్రవరా ఉత్పతన్తీతి ॥ ౬ ॥
tato ’dhastāc chata-yojanāntara iyaṁ pṛthivī yāvad dhaṁsa-bhāsa-śyena-suparṇādayaḥ patattri-pravarā utpatantīti.
[tato ’dhastaach chata-yojanaantara iyam prithivee yaavad dhamsa-bhaasa-shyena-suparnaadayah patattri-pravaraa utpatanteeti.]
Word-for-word
tataḥ adhastāt
—
beneath that
śata-yojana
—
of one hundred yojanas
antare
—
by an interval
iyam
—
this
pṛthivī
—
planet earth
yāvat
—
as high as
haṁsa
—
swans
bhāsa
—
vultures
śyena
—
eagles
suparṇa-ādayaḥ
—
and other birds
patattri-pravarāḥ
—
the chief among birds
utpatanti
—
can fly
iti
—
thus.
Blended reading (Sanskrit + English inline)
tato ’dhastāc chata-yojanāntara iyaṁ pṛthivī yāvad dhaṁsa-bhāsa-śyena-suparṇādayaḥ patattri-pravarā utpatantīti.
tataḥ adhastāt
beneath that
śata-yojana
of one hundred yojanas
antare
by an interval
iyam
this
pṛthivī
planet earth
yāvat
as high as
haṁsa
swans
bhāsa
vultures
śyena
eagles
suparṇa-ādayaḥ
and other birds
patattri-pravarāḥ
the chief among birds
utpatanti
can fly
iti
thus.
Below the abodes of the Yakṣas and Rākṣasas by a distance of 100 yojanas [800 miles] is the planet earth. Its upper limits extend as high as swans, hawks, eagles and similar large birds can fly.
Gauḍīya Ācāryas
Viśvanātha Cakravartī Ṭhākura
Gauḍīya
Translation
Below the abodes of the Yakṣas and Rākṣasas by a distance of 100 yojanas is the planet earth, whose upper limits extend as high as swans, hawks, eagles and similar large birds can fly.
This verse describes upper limit of Bhūrloka above the earth plane. Swans and other birds are transformations of earth.
My note
Source: vedabase.io