Adding in href

Signed-off-by: Mary Anthony <mary@blockstack.com>

_org/tokenholders.md

@@ -10,7 +10,7 @@ The information on this page is intended for **current Stacks (STX) token holder
 
 ## Find your token balance and unlock date
 
-{% include important.html content=" If you <strong>purchased Stacks tokens during Summer 2019</strong>, the form below will <strong>not</strong> work for your allocation. Please <a href='' target='_blank'>check your allocation using this tool instead</a>. "%}
+{% include important.html content=" If you <strong>purchased Stacks tokens during Summer 2019</strong>, the form below will <strong>not</strong> work for your allocation. Please <a href='https://explorer.blockstack.org/verifier' target='_blank'>check your allocation using this tool instead</a>. "%}
 
 During your the initial grant process, you should have submitted a public *Stacks (STX) address* (also known as a *wallet address*) to Blockstack. A STX address is a string of letters and numbers starting with an `SP` or `SM`, for example: `SM3KJBA4RZ7Z20KD2HBXNSXVPCR1D3CRAV6Q05MKT`