[Gulf Stream] Baltik Colors Vol.1 (艦隊これくしょん-艦これ-)
[Gulf Stream] Baltik Colors Vol.1 (Kantai Collection -KanColle-)

Doujinshi Link -> http://www.doujinshi.org/book/656297/Baltik-Colors-vol.1/
Toranoana Link -> http://www.toranoana.jp/mailorder/article/04/0030/16/54/040030165469.html
Melonbooks Link -> https://www.melonbooks.co.jp/detail/detail.php?product_id=19637