In Graff and Bukowska, 2005, the SERS spectra of enantiomeric and racemic Cysteine on silver electrodes are given. In their Figure (a), we can see the situ SERS spectrum of L-cysteine; the wavelengths of the peaks, which are relevant for our comparison, are given at: 670, 725, 890, and 1395 (cm -1 ). We can also note the presence of three peaks as in our Figure in the Fig.