Autumn poem from the Shin kokin wakashu (New Collection of Japanese Poems Old and New)

This poem is by Gishumon'in no Tango (late 12th-early 13th century) from the 13th-century imperial anthology Shin kokin wakashu, vol. 5, autumn poems section 2, and reads:

Wasureshina Naniwa no aki no yowa no sora
Koto ura ni sumu tsuki ha mirutomo

For other examples of calligraphy by Emperor Go-Nara, see lots 52 and 58.