Chris Gekker is one of my favourite trumpeters, for his many recordings as a soloist and with the American Brass Quintet (1 2 3), for his writings (see: one of my favourite articles about practicing trumpet) and for his book Articulation Studies.
Even though, as the title suggests, the book is intended to assist articulation, most of the exercises are built around scale patterns and many would work equally well slurred or tongued. Either way they are classics.
Exercise 1:
Exercise 2:
Exercise 13:
Exercise 25:
Exercise 24 (works well played immediately after ex. 25):
