A clue would be Gavrilo Princip, and the transcript of the Trial of the conspirators of the assassination of Archduke Ferdinand.
The Rare book of the Trial for British readers can be found by going to your local library, to say that you want a book held by the British Library and you need it borrowed to your local library so you can read it, it will take several months.
This isn't a book by a conspiracy nut but a honest appraisal of the trial notes!
It is called THE SARAJEVO TRIAL by W.A. Dolph Owings.
Page 34 is on download, please click on image again when it comes up to make bigger and clearer.
Freemasons are mentioned throughout the Trial, and as i have this rare book will happily download other pages in future where freemasons re mentioned.
The Master of the Black Hand was Dragutin Dimitrijevic, quote from first sentences of link" Also known as The Bee, Colonel Apis, No.6 or Most commonly, APIS", when you get to link please click on APIS, to show this is just another name for OSIRIS in Egyptian mythology!
The Book The Sarajevo Trial by W.A. Dolph Owing is used as a noted accurate account by historians the world over for research, another link to pages to this book can be found on the link below, when link shows image please click on image again to make larger:-
All masons like symbolism, this may be aligning a special day to the Sun with the Egyptian God stars, or in this case with the Black Hand Society they chose a very special day in Serbian history to assassinate Archduke Ferdinand, which started World War One, that was a deliberate use of St. Vitus Day.
In orde to understand exactly what went wrong back in the Summer of 1914, we need look no further than exmine the key alliances that happened between 1879 and 1907, ending with the Triple Entente.
In fact these treaties were alliances that the major nations signed in fear of each other declaring war, yet made all Europe vulnerable to a terrorist attack, bringing the powerful nations into an involuntary dance of death, and a war that no one wanted, yet were duty bound by the signed agreements.
St Vitus Day 1389, and the Battle of Kosovo Poyle marks the beginning of the Serbian Nation, the spirit of togetherness that saw the Serbian peoples unite against the Turkish invader.
Obviously the day changes if valued by the Julian or Gregorian Calendar, however 28th June 1914 is St. Vitus day, and there are grounds to speculate that this day was chosen that triggered W.W.1.