General reading on 13C T1 measurements in proteins: 91CPL41 , 92BIO5253 , 93JACS6333 , 95JMRB173-108 , 96BIO6116 , 96BIO14512 , 98JB165 , 99JACS2891 )
Relaxation T1 measurements of side-chain CH2 groups in uniformly 13C-labeled ubiquitin ( 03JB241-26)