It must be a shorthand way of writing what's in the previous bar: instead of writing all three triplets out, he's written one, with the '3' over it, saying it gets played thrice. As each chord needs to be staccato, he's put three dots over it, to signify each staccato.
As Laurence Payne's comment says, you've encountered one form of musical shorthand. There are a few layers of shorthand here so I'll break it down for you.
Stripping the first of the first measure of the second line of any shorthand markings, we have just a dotted eighth note.
Now we'll look at that slashy mark across the stem. It just means to subdivide ...
Bela Bartok was an Ethnomusicologist too.. he was known to have collected some gypsy songs, for example:
If you are searching for a book on this subject,
Bela Bartok's Studies in Ethnomusicology seems to be interesting:
That part is in the original (see the last two measures of the fourth page).
The problem could be that you have an arrangement of the piece (i.e., not the original, unabridged version).
Wait, slow down a minute. You mentioned tabs. Are you by any chance playing this on a guitar? If so, the editor might have decided to cut those two bars for their sheer ...