During its thirteen years of existence, the Rival featured 800 authors and their works from the fields of Croatian and world literature and arts.
He has authored the following titles: Riječki krug redom (1987), Pogledom u riječ (1987), Janko Polić Kamov – Selected Short Stories and Poems (1997), Dan velikih valova (prose and poetry by the Rival-generation, with the complete Rival bibliography 1988–2000, as well as the 1987–2001 series, co-authored with Goran Ušljebrka and Milan Zagorac, 2001), Pavica Julija Kaftanić (co-authored with Boris Zakošek, Lovorka Ruck and Igor Žic, 2005), Southerly Thoughts and Other Stories (An Anthology of Croatian Short Stories by Ksaver Šandor Gjalski, Janko Polić Kamov, Miroslav Krleža, Vladan Desnica, Ranko Marinković, Slobodan Novak, Ivan Aralica, Ivan Slamnig, Antun Šoljan and Nedjeljko Fabrio — selection by Mladen Urem, Damir Biličić and Želimir Galjanić, 2005) and Janko Polić Kamov, Dora Maar i hrvatska avangarda (Janko Polić Kamov, Dora Maar and Croatian Avantgarde, 2006).
Urem is frequent a contributor to the US literary journals Grand Street (New York City), Partisan Review (Boston), World Literature Today (Norman, Oklahoma) and Corner (Oakland, California), in which he has also published various works by the Croatian writers Janko Polić Kamov, Miroslav Krleža, Ivo Andrić and Ivan Goran Kovačić.
He has collaborated with the famous US authors and editors Deborah Treisman (1971), William Phillips (1907–2002), Robert Bingham (1966–1999) and others, as well as with the British historian Lucy Hughes-Hallett (1953).
He is a member of the Croatian PEN Center in Zagreb and works at the Rijeka State Archives, managing its Library and Publishing Department.