a cytidine(6-4)cytidine in DNA => a cytidine dimer in DNA + H(+)
a cytidine(6-4)cytidine in dna => a cytidine dimer in dna + h(+)
a cytidine(6-4)cytidine in DNA => a cytidine dimer in DNA + H(+)
a cytidine(6-4)cytidine in dna => a cytidine dimer in dna + h(+)