The verse Tobias quoted comes at the beginning of the web page.
– Part of that verse is missing and also the commas are in the wrong places. The following is the same verse in the Buddha Jayanthi Tipitaka edition, which is correct:
“Tattha tīṇi saṅkhatalakkhaṇāni tisso dukkhatā: uppādo saṅkhatalakkhaṇaṁ saṅkhāradukkhatāya dukkhatā ca, vayo saṅkhatalakkhaṇaṁ vipariṇāmadukkhatā ca, aññathattaṁ saṅkhatalakkhaṇaṁ dukkhadukkhatāya dukkhatā ca, imesaṁ tiṇṇaṁ saṅkhatalakkhaṇānaṁ..”
“Three saṅkhata lakkhaṇa correspond to three types of suffering (tisso dukkhatā):
(i) uppāda is a saṅkhata lakkhaṇa that corresponds to saṅkhāra dukkhatā. A saṅkhata arises due to (avijja paccaya) saṅkhāra. That itself takes effort (suffering). Furthermore, it will also lead to future suffering.
(ii) vayo is a saṅkhata lakkhaṇa corresponding to vipariṇāma dukkhatā. Any saṅkhata is destroyed (vaya) and that leads to vipariṇāma dukkhatā.
(iii) aññathatta is a saṅkhata lakkhaṇa corresponding to dukkha dukkhatā. Any saṅkhata undergoes unexpected changes (aññathatta) during existence and that is dukkha dukkhatā.