Sanjo-wasan (Three Books of Buddhist Hymns written in Japanese) (三帖和讃)
"Sanjo-wasan" is a collective term for Jodo-wasan (hymns of the Pure Land school), Koso-wasan (hymns about high-ranked priests), and Shozomatsu-wasan (hymns about three stages of the history of Buddhism), all of which were written in Japanese by Shinran.
Jodo-wasan (118 verses) and Koso-wasan (119 verses) are considered to have been written around 1248, and Shozomatsu-wasan (116 verses) is assumed to have been writtem around 1257.
Subsequently, they were often revised partially and also transcribed, until they were newly published by Rennyo together with Shoshin Nenbutsuge (the right version of verses for prayers) so that followers may use the publications at their devotional exercises in the morning and evening. "Shinran wasanshu" (literally, "Collection of Buddhist hymns written by Shinran in Japanese") with revisions and annotations by Ojun NABATA, a current writer, was published from Iwanami Bunko, followed by its wide version.