Hi Louise
In terms of official RDA, the meaning of "bound-with" is now restricted to the context of a collection.
I think the best approach for each of your volumes is to use the "facsimile part" elements.
Each of the facsimiles is made a "discrete component" of the volume because it is embodied in a specific set of pages marked by the original title page:
Volume (manifestation) has facsimile part "... Hf. 36".
Volume (manifestation) has facsimile part "... Hf. 37".
Volume (manifestation) has facsimile part "... Hf. 38".
Staying at the level of manifestation, each volume is also part of the series manifestation:
Volume (manifestation) is part of manifestation "Kraus Reprint ...".
Moving to Work and Expression, each volume is a collection aggregate that embodies the same content as the original publications combined. Each of the aggregated expressions can be found in its original publication and in the later aggregation, and at a broader level, in the reprint series as a whole.
Volume (manifestation) has expression manifested "Hf. 36 ...".
Volume (manifestation) has expression manifested "Hf. 37 ...".
Volume (manifestation) has expression manifested "Hf. 38 ...".
Orginal volume (manifestation) has expression manifested "Hf. 36 ...".
Series set (manifestation) has expression manifested "Hf. 36 ...".
Please note that "Hf. 36 ..." is an access point for an expression/work, while "... Hf. 36) is an access point for a manifestation.
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Gordon Dunsire
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