By references do you mean "from the X hoard or X collection"? I don't recall seeing any catalog or book references on NGC slabs. Excerpt from NGC's website: Pedigrees The discovery and / or verification of pedigrees is not included in the grading fee, so under most circumstances the submitter must provide supporting documentation (photocopies from auction catalogs, etc.) in order for a pedigree to be included on the label. Since the descriptive portion of the label is limited to five lines, the inclusion of a pedigree may require the elimination of other non-vital data. Pedigrees that typically can be requested include museum de-accessions, major private collections, important auctions, recognized hoards that are published (or that are verifiably on track to be published) and private labels. Additional Considerations Reference Ancient coins are attributed based upon the conclusions in standard references. In order to maintain a reasonable submission fee, and to avoid the problems associated with individual requests for different references, NGC Ancients typically does not include reference numbers on its labels. Exceptions to this rule include die identifications for decadrachms of Syracuse, and some other important coinages that have been exhaustively studied, and for which die identifications are both practical and universal. ... Unless they start using a much smaller font, there won't be enough room for all of the information we feel is important. Also, the additional information ("such-and-such hoard") requires paying for a higher submission level ($40 tier and up).
I'm not familiar enough with those coins to know whether Mytilene hektes & Bodenstedt's survey meet their criteria listed in the "Additional Considerations-- References" blurb above. I guess it does, and/or the submitter provided definitive references to NGC's satisfaction and requested that the reference be put on the label.
Thanks for pointing out my typo!! How kind of you @paddyman98 I am very aware that Mytilene was THE port of Lesbos....its amazing what wikipedia can tell you. So I see you are familiar with Bodenstedt, what is the significance of the attribution on the label. I wonder - the coin was bought off of ebay raw and submitted. Did you know it is quite rare, since you are familiar with Bodenstedt (a reference I don't have), can you tell me what is so specific that i warents the attribution on the label, is it the coin pictured in plates, one of the examples? Or it is so well known as that coin that can just go with it? I was reading that it only list 8 examples at the time of publish, and since some more have come to light (20) according to Asia Minor coins. Paddyman please share your expertise!
BTW I was reluctant to show the coin 'cuz I want to crack it out and and take proper photos. If you want to see some horrid photos of it be my guest you can get those from the NGC website.
Pecunem auction 30 has pre-slabbing images of that hekte. Interesting how NGC's pictures make it look polished . Pecunem's images always look very matte though. Their coins are usually much livelier in hand.
This coin is cataloged by Bodenstedt as #21 I want to share this webpage with you - http://www.coinproject.com/coin_detail.php?coin=269898
Here are most of the Bodenstedt listed Greek coins - I had it saved in favorites looking for a Greek coin with an owl image once. Thought it was a good reference. I want to share this webpage with you - http://www.coinproject.com/search_city_result.php?city=Mytilene®ion=LESBOS&type=1
