Check out those articles about baltic porter and Baltic Porter Day
In Polish:
Birofilia.org
Beerlovers
naTemat
Kilka Słów o Piwie
WP Finanse
Homebrewing.pl with baltic porter characteristics, ingredients, and home brewing tips.
Kompedium Piwa with style characteristics of baltic porter and smoked baltic porter.
Z Innej Beczki blog with their baltic porters reviews.
Wikipedia
Huge review of more than 150 baltic porters on Piwne Podróże blog.
In English
Beer Judge Certification Program baltic porter style guidelines.
Craft Beer and Brewing with tips for brewing baltic porter , how to brew baltic porter at home, style characteristics, brewing baltic porter, the Polish way and brewing hop forward baltic porter.
Kegerator with general knowledge about baltic porter.
Famous beer writes and historian Martyn Cornell deals with some myths about baltic porter history.
Profibeer about baltic porter history in Russia.
Top 50 baltic porters in the world according to RateBeer.
Top baltic porters and imperial/double baltic porters according to Untappd.
And 100 best baltic porters on Beer Advocate.