German Song is a lovely short piece from the book Russian School of Piano (Die Russische Klavierschule). I really like that this method book is entirely focused on perfecting the intoning technique — in simple terms: to make the piano "sing".
Lydia Kershner (1905 — 1968) was an Ukrainian/Soviet composer, but not much is known from her life. The Russian Conservatory of Music has this entry on her (translated with google translate): https://www-conservatory-ru.translate.goog/esweb/kershner-lidiya-mikhaylovna-1905-1968?_x_tr_sl=ru&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp
Sheet music for this piece:
Method book Russian School of Piano Playing book 1 part II (Hal Leonard)