I'm having difficulty interpreting a notice from the London Gazette from 1880. The notice is a call for the creditors of the late Samuel Mackenzie to contact the solicitors of the administratix with any claims they may have by a certain date. That all seems straightforward, but I don't understand the following part: "Pursuant to an Order of the High Court of Justice Chancery Division, made in an action in the matter of the estate of Samuel Mackenzie, deceased, Mackenzie v. Mackenzie, 1880, M., 20, the creditors of Samuel Mackenzie ...etc etc". Does this mean that he didn't appoint an administrator or that the administration of the will was contested by two members of the family? Does it mean that the will itself was contested? And what do M and 20 refer to? Any help would be gratefully received.