Marma Banjo 4 Strings GDR Germany Vintage and Rare | Reverb Italia
BANJO 6 CORDES DE MARQUE MARMA DES ANNÉES 70 - 80 | eBay
1960s East German Marma resonator banjo ukulele - YouTube
Frogmouth Guitars - Old Marma Banjo-Mandolin - we reset the neck angle so the strings were higher above the skin, then levelled, re-crowned and polished the frets, finally adjusting the bridge height