This collection of 12 trios by Johann Georg Albrechtsberger (1736-1809) was arranged for organ by Arthur William Marchant (1850-1921). The pedal part in some of the trios is technically demanding (in contrast to other compositions of Albrechtsberger), so I suspect that these are transcribed trios. Surely there is someone among you who can give us some references to the originals, if applicable.