As a student 40 years ago I wrote a thesis about all existing cello methods. Then I started writing my own method by putting all positive aspects of all methods together.
The music selection is the best I could find for each level progressing in well prepared steps, enjoyable to play.
Exercises are compact and to the point, only used when needed.
Volume 3 contains No 64-100 on 60 pages - Learning to shift from Half position over first, second, third to 4th position. All pieces are written in form of a cello duo to be able to play with a friend or teacher together - includes traditional songs, fiddle tunes and compositions by Offenbach, Bach, Carcassi, Tchaikovsky, Moore, , Boccerini, Boris Fomin and Kummer.
To each number are video cello lessons published on Patreon. The links click through when viewed on phone, tablet or computer.
There are also Youtube recordings of all pieces as Cello Duos with fingerings and bowings as in the Cello Method, see https://www.youtube.com/playlist?list=PLa4x_CVYDVRXAnJJ_6HeRujngwTZ8cMEd

ISBN 9781609746278. This is the second popular book of beautiful Celtic tunes compiled and arranged for the cello by Abby Newton. Most of the tunes in this collection are from her recent recordings, Castles Kirks and Caves and em>Ferintosh. The book is organized in three parts: Tunes, Sets, and Duos. The first part, Tunes, contains an assortment of twenty-eight tunes culled mostly from the well know Scottish and Irish traditional tune books including collections by Capt. Simon Fraser, Patrick McDonald, Niel Gow and James Oswald. The second part, Sets, consists of several tunes played in succession. Part three, Duos, includes two part scores (with treble and bass lines) that come mainly from James Oswald's Airs for the Seasons and Burke Thumoth's Collection of Scots and Irish Tunes 1745.