At this link 

https://www.quantconnect.com/data/tree/crypto/gdax/minute

 it shows ATOM, ALGO, and LINK as available pairs on GDAX with USD but if I try what I have below I get the following error.

linkusd = self.AddCrypto("LINKUSD", Resolution.Minute).Symbol kncusd = self.AddCrypto("KNCUSD", Resolution.Minute).Symbol

 

During the algorithm initialization, the following exception has occurred: ArgumentException : Symbol can't be found in the Symbol Properties Database: LINKUSD

ArgumentException : Symbol can't be found in the Symbol Properties Database: KNCUSD

 

Are some listed as available and not or am I accessing them incorrectly?

 

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