Questão jurídica principal
Whether the public-law appeal against the tax judgment was sufficiently reasoned under Art. 42 BGG.
Decisão extraída
The appeal did not engage with the decisive reasoning of the cantonal judgment and therefore lacked a sufficient substantiated challenge.
Fundamentação extraída
A mere reference to earlier correspondence and general assertions about double taxation or tax fairness is not enough; the appellants had to address the detailed findings on individual asset inflows and expenses.