Below is listed some preparatory reading that you can do if you have the time and inclination. Please note, that none of these should count as ‘required reading’.
Bhikkhu Bodhi, Connected Discourses of the Buddha, Wisdom Publications, 2000. Introduction to the Nidāna Saṃyutta, pp.515–526, and the discourses themselves, pp.533–620. You may have this book anyway, or wish to purchase it, as it is invaluable for the study of early Buddhism. You may be able to download a pdf copy from the internet. There are also some resources available online:
Bhikkhu Sujato’s guide to the Saṃyutta Nikāya, including ’The Book of Causation’ (Nidāna Saṃyutta).
All of Bhikkhu Bodhi’s translations of the discourses from the Book of Causation are available online here, along with Bhikkhu Sujato’s translations and many other resources.
Below is a pdf of a chapter from Choong Mun-Keat, Fundamental Teachings of the Buddha, on the comparison of the Pāli and Chinese versions of the Nidāna-saṃyutta (Chapter 6, Causal Condition). This will give you a sense of what is gained from looking at different versions of early Buddhist texts.
Finally, the first few pages of an important article by a Japanese scholar (Hajime Nakamura), which explains how we can see the development of the twelve nidānas formula in a discourse that is found in the Sutta Nipāta, which probably preserves a record of the Buddha’s teaching from a period early in his career, before he had developed the many lists and formulae that are so typical of most of the Nikāyas.