Ackermann H W, Caprioli T, Kasatiya S S
Can J Microbiol. 1975 Apr;21(4):571-4. doi: 10.1139/m75-080.
Phage VD13 possesses a large, elongated head and a long, non-contractile tail. It is active on group D streptococci and contains double-stranded DNA. The phage produces several rare kinds of head malformations, notably polymorphic mottled structures and giant heads which probably contain DNA.