All Digital Editions of the Manga Have Been Delisted as of 2019

(from ebookjapan):
Little Poko's daily life is full of interesting and mysterious things! The tomboyish and free-spirited Poko does things that make her gentle mom and dad say, "Oh no....... Poko" Included are three editions: the precious "Monthly Holp" edition, the "Ribon" edition in which Poko first appeared, and the slightly precocious "Shin Fujin Shinbun" edition.