When asked why he composed his dictionary of trigrams, Ross Eckler replied that it might be useful for crossword puzzle addicts or scrabble fans. Mostly, I think, he did it just for fun. Anyway, that's the only excuse I give for this assemblage of all-consonant tetragrams.
"Pure Consonant Tetragrams,"
Word Ways: Vol. 9
, Article 19.
Available at: http://digitalcommons.butler.edu/wordways/vol9/iss2/19