\begin{tikzpicture}[graph vertex/.style={draw, circle, minimum size=0.5cm}] \node[graph vertex, third] (v1) at (.50, 5.00) {1}; \node[graph vertex, second] (v2) at (2.50, 5.00) {2}; \node[graph vertex, fourth] (v3) at (5.00, 5.00) {3}; \node[graph vertex, third] (v4) at (4.00, 4.15) {4}; \node[graph vertex, fourth] (v5) at (1.00, 3.50) {5}; \node[graph vertex, third] (v6) at (5.50, 3.50) {6}; \node[graph vertex, first] (v7) at (2.80, 3.00) {7}; \node[graph vertex, third] (v8) at (1.40, 2.25) {8}; \node[graph vertex, second] (v9) at (4.00, 2.55) {9}; \node[graph vertex, third] (v10) at (5.50, 2.20) {10}; \node[graph vertex, second] (v11) at (2.90, 1.50) {11}; \node[graph vertex, third] (v12) at (4.20, 1.25) {12}; \node[graph vertex, fourth] (v13) at (5.50, 1.00) {13}; \node[graph vertex, fourth] (v14) at (1.00, .80) {14}; \node[graph vertex, third] (v15) at (2.80, .10) {15}; \node[graph vertex, fourth] (v16) at (4.50, .07) {16}; \graph { (v1) -- (v2), (v2) -- (v4), (v3) -- (v6), (v3) -- (v4), (v4) -- (v9), (v2) -- (v7), (v7) -- (v9), (v9) -- (v6), (v7) -- (v11), (v9) -- (v11), (v9) -- (v10), (v9) -- (v11), (v10) -- (v11), (v11) -- (v12), (v12) -- (v13), (v13) -- (v16), (v16) -- (v15), (v8) -- (v11), (v5) -- (v8), (v8) -- (v14), (v14) --[bend left] (v5), (v4) -- (v6), (v11) -- (v15), (v10) -- (v13), (v6) -- (v10) }; \end{tikzpicture}