Number | Name | Date | Kind |
---|---|---|---|
3186224 | Mair | Jun 1965 |
Number | Date | Country |
---|---|---|
1,110,175 | Apr 1968 | UK |
Entry |
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Article in "IZV Inst. Elektron," (Bulgaria), Vol. 5, 1971, pp. 167-172, by M. Marinov, A Contact Levelmeter with Transistor Converter in Decimal Code. |