Mainly looking at background research for the causes of the Revolutions that swept over Europe in 1848, and articles detailing key groups involved in the Revolutions.
for an European overview, perhaps the best point to start is Jonathan Sperber, The European Revolutions, 1848-1851, Cambridge University Press 2005 (1994).
In case you read German, there are numerous studies on the various risings in Baden, Prussia, Austria, Hungary, etc. Let me know and I can suggest a few.
for a more profound analysis into the labour problem and the identities i can propose you the work fo Samuel Hayat, you can fin his work in academia.edu and most of his articles are free to download
Though not solely and specifically addressing your topic, Philip Mansel's 'Paris Between Empires 1814-1852: Monarchy and Revolution' (London: Phoenix Press 2001/2003), particularly Chapter 13: 'The People 1844-1852' (pp. 383-422), discusses France in the pan-European context regarding the 1848 Revolution. Other chapters in the book provide greater cultural context as well.
I researched and studied somewhat the 1848-1849 revolutions in the context of the Austro-Hungarian Empire. To me it appears that one of the main causes was the ethnic diversity that dwelled in that realm. Typical examples were the Hungarians and Slovaks dissatisfaction with Vienna and also the brutal way the Austrians and Hungarians were trying to force upon other ethnic groups their cultures and languages.
Here are some interesting references:
Verdery, Katherine. "Internal colonialism in Austria‐Hungary." Ethnic and Racial Studies 2.3 (1979): 378-399.
She starts this article saying that “marked ethnic tensions existed in the Habsburg territories and Transylvania. These caught fire in the 1780s, exploded violently and unsuccessfully in 1848, and smoldered on into the 20th century…”
Berger, Helge, and Mark Spoerer. "Economic crises and the European revolutions of 1848." The Journal of Economic History 61.02 (2001): 293-326.
This article’s abstract claims a different main reason: “Recent historical research tends to view the 1848 revolutions in Europe as caused by a surge of radical ideas and by long-term socioeconomic problems. However, many contemporary observers interpreted much of the upheaval as a consequence of short- term economic causes, specifically the serious shortfall in food supply that had shaken large parts of the Continent in 1845–1847, and the subsequent industrial slump. Applying standard quantitative methods to a data set of 27 European coun-tries, we show that it was mainly immediate economic misery, and the fear thereof, that triggered the European revolutions of 1848.”
And this is a book that analyses the social, economic and political developments in Austria-Hungary between 1683 and 1867; in 1867 the Habsburg monarchy was forced to split the empire and allow the Hungarians a much greater political autonomy, as result of the so called Ausgleich agreement between Vienna and Budapest. Thus, in fact, if the Hungarians were defeated in 1848, they finally win in 1867.
Evans, Robert John Weston. Austria, Hungary, and the Habsburgs: Central Europe c. 1683-1867. Oxford University Press, 2006.
I do not have an answer for all of Europe, but according to some price indices I checked for quite another reason, the Dutch Costs of Living rose with no less than 43,5% in 1845, to stabilize after that year on that dramatic level. By stable wage levels that is a good reason for protests, I think.
I think the underlying reasons of the revolution of 1848 are due to acquired concept, by the people, of equality and freedom derived from the French Revolution; the birth of radical parties (publication of the Manifesto of Karl Marx) and the rise of nationalism.The most widely read author of those times was Lamartine.
For this you can look for the cause, singular, of the 1848 revolution but I believe you'd be chasing your tail a while as there are a number of reasons, laid out neatly by Bruno, for it. You could use novels, this is a great time for publication, as the authors are trying to convey their beliefs in their works so you can get a good insight from there. Everything is a source Alex, from posters to magazines, but I'm afraid this is one of those essays where they are looking for your research methods and reasoning skills for the most part.
pick a side you like, an author who's work you agree with and then go from there. There really is no right or wrong answer as long as you argue your points well.
You might be interested in this "classical" study: Quentin-Bauchart, P. (1920). Crise sociale de 1848: les origines et la révolution de février. Paris: Hachette.
Revisiting this narrative with new methods and focuses might be stimulating.
Among the more recent scholarly literature, you might also like:
Maurizio GRIBAUDI et Michèle RIOT-SARCEY, 1848, la révolution oubliée, Paris, La Découverte, 2008 (and all the rest of M. Gribaudi's production on the subject)
Reviewed here:
http://rh19.revues.org/4032
See also: The Second French Republic 1848-1852: A Political Reinterpretation by Christopher Guyver, Springer, 2016 - 366 pages
Recent about Rome, with full bibliography:
Roma senza il Papa: La Repubblica romana del 1849 by Giuseppe Monsagrati
Daniele Manin and the Venetian Revolution of 1848-49
Paul Ginsborg, CUP , 1979 - 417 pages
There are also many references about the Balkans to be read, around the need of a revisitation of the interpretation of the link between the rise of nationalisms and revolts.