As Salaamu Alaykum,
The Tafriqa of Shehu Uthman ibn Fuduye` is an early text on the science of Sufism, written during the beginning of the reform movement that resulted in the establishment of the SOKOTO CALIPHATE, the largest most successful Islamic polity in Africa.
The text is called:
at-Tafriqa Bayna `Ilm ‘t-Tasawwuf Alladhi Li ‘t-Takhalluq wa Bayna `Ilm ‘t-Tasawwuf Alladhi li ‘t-Tahaqquq wa Madaakhil Iblees.
(The Distinction Between the Science of Tasawwuf for Character Transformation and the Science of Tasawwuf for Divine Realization & the Incursions of Ibless into the Souls).
You can read Shaykh Muhammad Shareef’s translation Here>>