Ferskeytt
Ferskeytt (literally 'four-cornered') is an Icelandic stanzaic poetic form. It is a kind of quatrain, and probably first attested in fourteenth-century "rímur" such as "Ólafs ríma Haraldssonar". It remains one of the dominant metrical forms in Icelandic versifying to this day. "Ferskeytt" comprises odd-numbered, basically trochaic lines with four stresses in the pattern / x / x / x /, alternating with even-numbered trochaic lines with three stresses in the pattern / x / x / x. In each line, one unstressed syllable may be replaced with two unstressed syllables. Stanzas are normally of four lines, and rhyme aBaB. In the first  line, two heavily-stressed syllables alliterate with the first heavily-stressed syllable of the second line, and so on in the usual alliterative pattern of Germanic alliterative verse. An example of the form is this verse by Jónas Hallgrímsson, with a translation into the same metre by Dick Ringler. Alliteration is emboldened and rhyme is "italicised": There are many variations on "ferskeytt", whose common principle is that they are quatrains with some kind of alternate rhyme. A poem in this metre is called a "ferskeytla" ('four-cornered [poem]'). Metres which share these properties belong to the "ferskeytluætt" ('ferskeytla-family'). Ferskeytt