Using this as an excuse to talk about a few of my current favourite sources, fair warning a lot of this will be in dutch
Historical / specifically paganism
heidense heiligdommen - Judith Schuyf
This book is honestly my favourite source she compiles a lot of evidence and if you read anything here, this one is probably the best one, judith also has a blog where she posts related articles sometimes.
Noord holland in het eerste millennium - published by huis van hilde
all of huis van hilde is amazing and these are free and available as pdfs. they have a lot of publications in English as well definitely worth checking out they also have archeological an archive [chapter about animal symbolism is available in English here ]
Heilige bronnen in de lage landen - Linda Wormhoudt
This is one of those books where it is not as historically informed or acedemic as the previous two which has it's perks and it's downsides. Very interesting if you want to get ideas for things to incorporate into your own praxis as there's also talk of a verity of people's praxis in there.
Wodan's mythical birds - Nicolay, Johan; van Eerden, R.A
Acedemic paper about wodan's birds and symbolism in archological finds available here one of these authors also worked on noordholland in het eerste millennium
This site has started to use ai which is ashame bc their work is honestly quite good and you can really specifically search for this to a locality or time period. Hopefully tgey drop it soon but i did want to mention it upfront.
Feel like i have to mention this well refrenced book but anything that has dutch sagas if you connect to any of them that's honestly an amazing jumping off point in my opinion
Bonus books that i have not gotten to read yet but am curious about
Woden a historical companion - Stephen Pollington
North sea water in my veins - Imelda Almqvist
De Atlantische Edda - pieter jansen
This creature doesn't bite!! Come and talk about sources with me i love hearing about people's interpertations! And practices!