https://scholarship.richmond.edu/mathcs-faculty-publications/119/
"Difference Sets in Abelian 2-Groups" by James A. Davis
Examples of difference sets are given for large classes of abelian groups of order 22d + 2. This fills in the gap of knowledge between Turyn's exponent...
difference setsjames aabeliangroupsdavis
https://www.compadre.org/PICUP/exercises/exercise.cfm?A=FDMFA
PICUP Exercise Sets: Finite Difference Method and Simple Pendulum
finite difference methodsimple pendulumpicupexercisesets