Problem in reading Research Paper

Hey guys, I am new to Deep Learning and was reading RNNs from Deep Learning by Ian Goodfellow. I was unable to understand LSTMs from the book, So I thought of reading first original paper on LSTM ( Hochreiter and Schmidhuber, 1997) will help me. Now I can't even figure out the notation on 2nd page, and what kind of network they are forming, if I can't figure out introductory paper, How will I be able to read papers with …

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