The Daf B'Iyun - Berachos Perek 1: Concise notes that develop the major topics of each daf (Volume 1)

This book is meant to add a level of depth to one's study of "the Daf Gemara" by providing a brief explanation of various commentaries and extra "marei mekomos" (sources for further research) on the major topics of each Daf. An extra emphasis is put on topics that are somewhat difficult to find in the most commonly used commentaries and books written as aids to the Daf.