Complex sentence: Seatrade publishes two quarterly magazines-- "Seatrade Maritime Review" and "Seatrade Cruise Review", in addition to a number of separate supplements to cover geographical areas, industry sectors and third party magazines.
Split into simpler sentences: Seatrade publishes two quarterly magazines-- "Seatrade Maritime Review" and "Seatrade Cruise Review". In addition, the brand produces a number of separate publications to cover geographical areas, industry sectors and third party magazines.