Complex sentence: In geometry, he enumerated and published a list of 25 convex uniform honeycombs (The tessellations of regular and semiregular polyhedra in three dimensional space) in 1905, the most complete list published until 1991 when Norman Johnson completed the full list of 28 forms.
Split into simpler sentences: In geometry, he enumerated and published a list of 25 convex uniform honeycombs in 1905 (the tessellations of regular and semiregular polyhedra in three dimensional space). This was the most complete list published until approximately 1991 when Norman Johnson completed the full list of 28 forms.