What is the best quality controlled LIMITED QTY-Dinucleotide Standards Formamido Cytidine Dimer d (PfpC) (50 µg)?

The LIMITED QTY-Dinucleotide Standards Formamido Thymine Dimer d from Ncbi publications supplied next week by Gentaur is the best choice. The catalog number is 801212 and the price is 66 EUR.