Information: - World Book Day or World Book and Copyright Day (also known as International Day of the Book or World Book Days) is a yearly event on April 23rd, organized by the United Nations Educational, Scientific and Cultural Organization (UNESCO), to promote reading, publishing and copyright. In the United Kingdom, the day is recognized on the first Thursday in March. World Book Day was celebrated for the first time on 23 April 1995. - The Territory of Nevada was an organized incorporated territory of the United States that existed from March 2, 1861, until October 31, 1864, when it was admitted to the Union as the State of Nevada. - Caroline Lawrence (born 1954) is an English American author, best known for "The Roman Mysteries" series of historical novels for children. The series is about a Roman girl called Flavia and her three friends: Nubia (a freed slave girl), Jonathan (a shunned Jewish boy) and Lupus (a beggar boy without a tongue). The series has won numerous awards and has been published in many different languages worldwide. In March 2010, Lawrence was commissioned to write another history mystery series of books called The Western Mysteries, set in Virginia City, Nevada Territory in the early 1860s. - The Code of Romulus is a children 's novella by Caroline Lawrence , published in 2007 to celebrate the 10th anniversary of World Book Day . It is a re-publication of the short story Bread and Circuses that appeared in the anthology The Mammoth Book of Roman Whodunits published in 2003 . The story takes place in Ostia in November 79 AD , between the events of the fifth and sixth books ( The Dolphins of Laurentum and The Twelve Tasks of Flavia Gemina . ) - The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign country in western Europe. Lying off the north-western coast of the European mainland, it includes the island of Great Britain (the name of which is also loosely applied to the whole country), the north-eastern part of the island of Ireland, and many smaller islands. Northern Ireland is the only part of the UK that shares a land border with another sovereign statethe Republic of Ireland. Apart from this land border, the UK is surrounded by the Atlantic Ocean, with the North Sea to its east, the English Channel to its south and the Celtic Sea to its south-south-west, giving it the 12th-longest coastline in the world. The Irish Sea lies between Great Britain and Ireland. With an area of , the UK is the 78th-largest sovereign state in the world and the 11th-largest in Europe. It is also the 21st-most populous country, with an estimated 65.1 million inhabitants. Together, this makes it the fourth most densely populated country in the European Union. - The Roman Mysteries is a series of historical novels for children by Caroline Lawrence. The first book, "The Thieves of Ostia", was published in 2001, finishing with "The Man from Pomegranate Street", published in 2009, and 17 more novels were planned, plus a number of "mini-mysteries" and companion titles. What is the relationship between 'the code of romulus' and 'the roman mysteries'?
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series