noun
piece of writing; poem; essay; story
Counter for a single literary work such as a poem, essay, or short story. Often used in formal or literary contexts.
彼は一篇の詩を朗読した。
He recited a poem.
この短編集には一篇の作品が収められている。
This short story collection contains one piece.
一冊 is a general counter for books or bound volumes, while 一篇 counts individual literary works within a volume or as standalone pieces.
Combination of 一 (one) and the counter 篇 (for literary works). The reading いっぺん follows regular rendaku and gemination rules.