URIs for each Part:

https://docs.oasis-open.org/office/OpenDocument/v1.4/csd01/part1-introduction/OpenDocument-v1.4-csd01-part1-introduction.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/csd01/part2-packages/OpenDocument-v1.4-csd01-part2-packages.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/csd01/part3-schema/OpenDocument-v1.4-csd01-part3-schema.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/csd01/part4-formula/OpenDocument-v1.4-csd01-part4-formula.odt

Latest stage:

https://docs.oasis-open.org/office/OpenDocument/v1.4/OpenDocument-v1.4-part1-introduction.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/OpenDocument-v1.4-part2-packages.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/OpenDocument-v1.4-part3-schema.odt
https://docs.oasis-open.org/office/OpenDocument/v1.4/OpenDocument-v1.4-part4-formula.odt