The topics grew out of citizen information requests through NARA or the US Mint, and current personal research where specific results can be identified. An example is "Additional Confirmation of Large Berry Half Cents as Contemporaneous Pieces." where locating the supporting material was part of the Restrikes, Novodels and Collector Coins research, but is applicable to those who collect half cents and specifically the novodel proofs of the 1840s. (Commonly called "restrikes.")
"Proof Coin Manufacturing Methods to the Present" is an article that explains how "proof" coins were made during different eras at the US Mint. Production methods differed, and understanding this can help separate authentic "proofs" from proof-like, imitation and non-proof coins. To a certain extent, it can be combined with the intervals of proof die repolishing identified in my 1936-1942 book to place limits on the number of pieces made before a proof die required refacing.